You Can Use Vive And Rift Simultaneously On One PC

[Simon Ayres]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

 

[kcarbotte]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

 

[Simon Ayres]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

 

[kcarbotte]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

 

[Simon Ayres]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

Hook up both HMDs to the same card as if you are running two monitors, enable SLI, run the same games. Failing that, attempt to contact the original poster to verify you are not missing a setting and are running the same drivers and OS, try again.

 

[kcarbotte]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

Hook up both HMDs to the same card as if you are running two monitors, enable SLI, run the same games. Failing that, attempt to contact the original poster to verify you are not missing a setting and are running the same drivers and OS, try again.

Sli has literally zero benefit in vr. It doesn't work at all, as per Nvidia.
Having two cards in sli doesn't have any benefit over a single card.
The only test I was doing was to verify the ops claim of being able to plug in one headset per card, which does not work.

Had the claim of sli not been made, I would have never even tested it. Period.
Sli does not work for vr, either way you slice it.

 

[Simon Ayres]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

Hook up both HMDs to the same card as if you are running two monitors, enable SLI, run the same games. Failing that, attempt to contact the original poster to verify you are not missing a setting and are running the same drivers and OS, try again.

Sli has literally zero benefit in vr. It doesn't work at all, as per Nvidia.
Having two cards in sli doesn't have any benefit over a single card.
The only test I was doing was to verify the ops claim of being able to plug in one headset per card, which does not work.

Had the claim of sli not been made, I would have never even tested it. Period.
Sli does not work for vr, either way you slice it.

in neither the post or video does he claim that he is plugging a HMD in to each card

 

[EddieF430]

Maybe don't run the gpus in sli, but allocate the hmd's to a different gpu?

 

[kcarbotte]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

Hook up both HMDs to the same card as if you are running two monitors, enable SLI, run the same games. Failing that, attempt to contact the original poster to verify you are not missing a setting and are running the same drivers and OS, try again.

Sli has literally zero benefit in vr. It doesn't work at all, as per Nvidia.
Having two cards in sli doesn't have any benefit over a single card.
The only test I was doing was to verify the ops claim of being able to plug in one headset per card, which does not work.

Had the claim of sli not been made, I would have never even tested it. Period.
Sli does not work for vr, either way you slice it.

in neither the post or video does he claim that he is plugging a HMD in to each card

Actually, that's exactly what he claimed... in both the video and the post.

https://youtu.be/zfXcdufaIvo?t=103

"Well, with the recent arrival of my Vive, I've now found an added bonus of this configuration - having the extra HDMI port (2 total) means I can operate the units simultaneously!"

- GTX 970s only have on HDMI port, so regardless of him saying it directly or not, he's said right there that both graphics cards are being used.


The OP also confirmed in the comments that he has the Vive in the first GPU and the Rift in the second GPU.
"For me, I have the Vive into Gfx card #1, Rift DK2 into Gfx card #2. Works easily that way, but you do have to be careful with what games you pick to get them to operate. Not all combinations are great. Also, users would want to use Voicemeeter or similar to route the audio appropriately."

https://www.reddit.com/r/oculus/comments/4dy3di/sli_bonus_two_hmds_at_same_time_rift_vive/d1zf10i


Satisfied yet?

 

[kcarbotte]

Maybe don't run the gpus in sli, but allocate the hmd's to a different gpu?

That is exactly what was done...

 

[Simon Ayres]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

Hook up both HMDs to the same card as if you are running two monitors, enable SLI, run the same games. Failing that, attempt to contact the original poster to verify you are not missing a setting and are running the same drivers and OS, try again.

Sli has literally zero benefit in vr. It doesn't work at all, as per Nvidia.
Having two cards in sli doesn't have any benefit over a single card.
The only test I was doing was to verify the ops claim of being able to plug in one headset per card, which does not work.

Had the claim of sli not been made, I would have never even tested it. Period.
Sli does not work for vr, either way you slice it.

in neither the post or video does he claim that he is plugging a HMD in to each card

Actually, that's exactly what he claimed... in both the video and the post.

https://youtu.be/zfXcdufaIvo?t=103

"Well, with the recent arrival of my Vive, I've now found an added bonus of this configuration - having the extra HDMI port (2 total) means I can operate the units simultaneously!"

- GTX 970s only have on HDMI port, so regardless of him saying it directly or not, he's said right there that both graphics cards are being used.


The OP also confirmed in the comments that he has the Vive in the first GPU and the Rift in the second GPU.
"For me, I have the Vive into Gfx card #1, Rift DK2 into Gfx card #2. Works easily that way, but you do have to be careful with what games you pick to get them to operate. Not all combinations are great. Also, users would want to use Voicemeeter or similar to route the audio appropriately."

https://www.reddit.com/r/oculus/comments/4dy3di/sli_bonus_two_hmds_at_same_time_rift_vive/d1zf10i


Satisfied yet?

You misquoted him, he said "with the extra HDMI cable" but I do see what you mean though you are missing one critical factor, seeing as the vive has display port it is within the realm of reason to assume that the vive is plugged into said display port as this would leave the hdmi as an extra port. His choice of wording is a little misleading but he does not state that the are both plugged in via HDMI nor that they are plugged in to separate cards.

Edit: I should also state that as he has said he has them plugged in to both cards and this would not work with SLI but he has it working so the logical hypothosys is that SLI is off and he is just unaware or is aware and failed to mention that he disabled it.

Him being unaware is the most logical conclusion as all it takes for sli to disable is a driver update

But at least I know why you were not understanding my argument, though it does still stand.

 

[kcarbotte]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

Hook up both HMDs to the same card as if you are running two monitors, enable SLI, run the same games. Failing that, attempt to contact the original poster to verify you are not missing a setting and are running the same drivers and OS, try again.

Sli has literally zero benefit in vr. It doesn't work at all, as per Nvidia.
Having two cards in sli doesn't have any benefit over a single card.
The only test I was doing was to verify the ops claim of being able to plug in one headset per card, which does not work.

Had the claim of sli not been made, I would have never even tested it. Period.
Sli does not work for vr, either way you slice it.

in neither the post or video does he claim that he is plugging a HMD in to each card

Actually, that's exactly what he claimed... in both the video and the post.

https://youtu.be/zfXcdufaIvo?t=103

"Well, with the recent arrival of my Vive, I've now found an added bonus of this configuration - having the extra HDMI port (2 total) means I can operate the units simultaneously!"

- GTX 970s only have on HDMI port, so regardless of him saying it directly or not, he's said right there that both graphics cards are being used.


The OP also confirmed in the comments that he has the Vive in the first GPU and the Rift in the second GPU.
"For me, I have the Vive into Gfx card #1, Rift DK2 into Gfx card #2. Works easily that way, but you do have to be careful with what games you pick to get them to operate. Not all combinations are great. Also, users would want to use Voicemeeter or similar to route the audio appropriately."

https://www.reddit.com/r/oculus/comments/4dy3di/sli_bonus_two_hmds_at_same_time_rift_vive/d1zf10i


Satisfied yet?

You misquoted him, he said "with the extra HDMI cable" but I do see what you mean though you are missing one critical factor, seeing as the vive has display port it is within the realm of reason to assume that the vive is plugged into said display port as this would leave the hdmi as an extra port. His choice of wording is a little misleading but he does not state that the are both plugged in via HDMI nor that they are plugged in to separate cards.

Edit: I should also state that as he has said he has them plugged in to both cards and this would not work with SLI but he has it working so the logical hypothosys is that SLI is off and he is just unaware or is aware and failed to mention that he disabled it.

Him being unaware is the most logical conclusion as all it takes for sli to disable is a driver update

But at least I know why you were not understanding my argument, though it does still stand.

There's no logical reason to assume that his use of "the extra HDMI cable" means he used the DisplayPort cable. More likely he misspoke and meant to say extra HDMI port, considering he's talking about having two cards, and the bonus unexpected benefit that he discovered.

I don't know why you feel it necessary to argue with me here. There's no assumption needed. I know for a fact he was using two cards. There's pictures of it on another website, I'm just not willing to use those as they weren't provided to me.
http://uploadvr.com/you-can-run-two-vr-headsets-simultaneously-on-a-single-computer-heres-what-youll-need/

Obviously SLI was disabled, for him.

I demonstrated that you can in fact use one card with the mini-DP cable, but the OP was in fact using two HDMI cables and two GPUs.

Again, the point of the article was simply to prove or disprove the idea of using two headsets on one system.
I showed that A) It can be done. B) It can be done with one card using mini-DP C) it can't be done with SLI enabled using the HDMI ports from each GPU, as the OP claimed D) The the Vive does not work from the second GPU. SteamVR driver doesn't communicate with the headset. E) after reviewing comments I realized that I forgot to test the opposite configuration, with the Vive in GPU1 and the Rift in GPU2 - after verification that this worked the post was updated.

At no point was I trying to make SLI improve the performance of the system, so there's no point in trying it out in this case. We don't have proper tools to record VR metrics yet, so there's really no point. FRAPS was used as an example, but we need something more suited to VR before we go chasing the best performance configurations. Not to mention, VR doesn't support traditional SLI and never will. VR SLI is not implemented into any current games, so that's a moot point too.

There's no reason to think that two HMDs won't work with SLI enabled, but there's plenty of reason to believe that it won't help with performance at all, and until we're equipped to prove that one way or another, we're not opening that can of worms.

The negative that you seem hellbent on insisting that I'm not able to prove, is that you can't use the HDMI port on the second card when SLI is enabled. A fact that you yourself agreed to.

 

[Simon Ayres]

You don't seem to be understanding, with sli enabled the second card can not but used to run a display, this is a limitation of SLI.

The cards not running SLI you can not get each card to run a HMD.

But neither of those things where claimed.

SLI enabled running 2 HMDs where what was claimed, you said you couldn't get it to work so therefor it doesn't work but you did not use the same test parameters there for your test is flawed as 1 different parameter could cause many mitigating factors.

To test things effectively you need to remove as many variables as possible or you can never say if your test is a success or failure.

Yes you could make the argument about CPU and RAM and MoBo but these are fairly standard parts that do not suffer overly much from things like compatibility issues. The parameters that should be kept the same from test to test are things that are prone to compatibility issues GPU, OS, Drivers, Software (in this case games)

And even after accounting for these variables if you fail you should then attempt to contact the origin to see if there is something you are missing or something he omitted from his write up (like he may have had to disable SLI for it to work.

Only after all of this can you make the claim that it doesn't work.

I went back and read what I wrote and I finally understand what you're going on about.
The wording using was unclear, but as I have stated repeatedly, I tested with and without SLI enabled.

But regardless, the point was to prove or debunk the orrigianl poster's claim that SLI lets you do this, which it does not. SLI needs to be disabled, and even when you do that, you need the Rift in the second GPU. The VIve does not work from a second GPU with or without SLI enabled.

The part that I said doesn't work has nothing at all to do with the games. You can't start the games before the HMDs are detected. The games are not a variable as you keep aluding to.

The variables being tested were:
can you hook up two HMDs to one PC? Do you need two GPUs? Does this work with SLI as claimed? What procedure is needed to make it work if you can?

The game performance doesn't matter because I didn't have a second person to play with the games. That was never the point. The game selection doesn't matter either, because it either displays or it doesn't.

Again, you can not "debunk" something when using different test parameters, that is not how science works.

What exactly do you want me to test? Please lay it out, because I'm seriously not following you.
Either be more clear, or leave this be. This is starting to be really irratating. What exactly do you think is such a "different test parameter"?

You pointed out yourself that SLI doesn't enable the other GPU outputs. I showed that to be the case, and I also demonstrated taht you can't connected the Vive to the second GPU regardless.

Hook up both HMDs to the same card as if you are running two monitors, enable SLI, run the same games. Failing that, attempt to contact the original poster to verify you are not missing a setting and are running the same drivers and OS, try again.

Sli has literally zero benefit in vr. It doesn't work at all, as per Nvidia.
Having two cards in sli doesn't have any benefit over a single card.
The only test I was doing was to verify the ops claim of being able to plug in one headset per card, which does not work.

Had the claim of sli not been made, I would have never even tested it. Period.
Sli does not work for vr, either way you slice it.

in neither the post or video does he claim that he is plugging a HMD in to each card

Actually, that's exactly what he claimed... in both the video and the post.

https://youtu.be/zfXcdufaIvo?t=103

"Well, with the recent arrival of my Vive, I've now found an added bonus of this configuration - having the extra HDMI port (2 total) means I can operate the units simultaneously!"

- GTX 970s only have on HDMI port, so regardless of him saying it directly or not, he's said right there that both graphics cards are being used.


The OP also confirmed in the comments that he has the Vive in the first GPU and the Rift in the second GPU.
"For me, I have the Vive into Gfx card #1, Rift DK2 into Gfx card #2. Works easily that way, but you do have to be careful with what games you pick to get them to operate. Not all combinations are great. Also, users would want to use Voicemeeter or similar to route the audio appropriately."

https://www.reddit.com/r/oculus/comments/4dy3di/sli_bonus_two_hmds_at_same_time_rift_vive/d1zf10i


Satisfied yet?

You misquoted him, he said "with the extra HDMI cable" but I do see what you mean though you are missing one critical factor, seeing as the vive has display port it is within the realm of reason to assume that the vive is plugged into said display port as this would leave the hdmi as an extra port. His choice of wording is a little misleading but he does not state that the are both plugged in via HDMI nor that they are plugged in to separate cards.

Edit: I should also state that as he has said he has them plugged in to both cards and this would not work with SLI but he has it working so the logical hypothosys is that SLI is off and he is just unaware or is aware and failed to mention that he disabled it.

Him being unaware is the most logical conclusion as all it takes for sli to disable is a driver update

But at least I know why you were not understanding my argument, though it does still stand.

There's no logical reason to assume that his use of "the extra HDMI cable" means he used the DisplayPort cable. More likely he misspoke and meant to say extra HDMI port, considering he's talking about having two cards, and the bonus unexpected benefit that he discovered.

I don't know why you feel it necessary to argue with me here. There's no assumption needed. I know for a fact he was using two cards. There's pictures of it on another website, I'm just not willing to use those as they weren't provided to me.
http://uploadvr.com/you-can-run-two-vr-headsets-simultaneously-on-a-single-computer-heres-what-youll-need/

Obviously SLI was disabled, for him.

I demonstrated that you can in fact use one card with the mini-DP cable, but the OP was in fact using two HDMI cables and two GPUs.

Again, the point of the article was simply to prove or disprove the idea of using two headsets on one system.
I showed that A) It can be done. B) It can be done with one card using mini-DP C) it can't be done with SLI enabled using the HDMI ports from each GPU, as the OP claimed D) The the Vive does not work from the second GPU. SteamVR driver doesn't communicate with the headset. E) after reviewing comments I realized that I forgot to test the opposite configuration, with the Vive in GPU1 and the Rift in GPU2 - after verification that this worked the post was updated.

At no point was I trying to make SLI improve the performance of the system, so there's no point in trying it out in this case. We don't have proper tools to record VR metrics yet, so there's really no point. FRAPS was used as an example, but we need something more suited to VR before we go chasing the best performance configurations. Not to mention, VR doesn't support traditional SLI and never will. VR SLI is not implemented into any current games, so that's a moot point too.

There's no reason to think that two HMDs won't work with SLI enabled, but there's plenty of reason to believe that it won't help with performance at all, and until we're equipped to prove that one way or another, we're not opening that can of worms.

The negative that you seem hellbent on insisting that I'm not able to prove, is that you can't use the HDMI port on the second card when SLI is enabled. A fact that you yourself agreed to.

lol fair enough, I didn't know you got it to work and updated the article accordingly.