Question ASRock B450 doesn't support 2 Nvidia GPU's?

[X-87]

Today I built a PC, everything went fine, everything was correctly plugged and installed in every port etc, but the problem arises when I insert either one of my two gpus into the PCIe 16 port (or whatever it is called), the mobo won't recognize it or neither Asus's driver software. It has the LED's working whole time and I can boot to Windows etc, but no display coming from any of the all 5 different ports (all the cables do work), so is ASRock B450 Steel Legend motherboard incompatible with two Nvidia GPUs? Or with 2 totally different Nvidia GPUs? Or is the secondary PCIe 16 port broken on mt motherboard, or what? When I swapped the GPU's for a test, Asus GPU tweakII said instantly "No VGA driver installed." (first time it didn't say anything) after booting to Windows, and would not let me to open the app but after few minutes waiting. My GPUs are GTX 1080 A8C (Not OC) and GTX 1070 08C (overclockable). Tried to search for solution from internet, someone said for a similar case that you need to use XMP in BIOS and something like that so the ram speeds go up to where they should be so other gpu would be recognizeable. Whaaaat? PC part picker wouldn't let me pick second gpu, and ASRock website says about compatibility with dual AMD gpu as CrossFireX or something (didn't understand that part at all). I can't understand the ASRock website because my poor English and PC knowledge.
Parts:
https://pcpartpicker.com/list/qzxsp8

Thanks in advance!!

 

[Phaaze88]

Asrock B450 Steel Legend supports AMD XFire, meaning you can link multiple identical gpu models(2x RX 580s, for example) for extra performance - but this performance gain varies widely.
The Nvidia version of this is called SLI - again, the models must be identical, and it doesn't matter what the brand is.

Are you trying to SLI on a XFire only mobo? Well, even if that were the case, you have 2 different cards...

It is possible to run both cards unlinked, but there's no real reason to do that.
So why do you need to run both a 1080 and a 1070?

 

[kerberos_20]

PCIe slots:
PCIE1 (PCIe 3.0 x16 slot) is used for PCI Express x16 lane width graphics cards.
PCIE4 (PCIe 3.0 x16 slot) is used for PCI Express x4 lane width graphics cards.
* If M2_1 is occupied, PCIE4 will be disabled.

 

[deepfabry]

I also would like to have more news about it, I also have an asrock steel legend but x570 version and currently a super rtx 2070 super and I would like to know if in the future I could combine an identical gpu for NVlink , on the official website it only refers to crossfire now I don't know if it's just a question of official license and in reality it works too .... or you can install an alternative bios (maybe taichi?) has anyone tried on these cards or has any news?

 

[X-87]

Asrock B450 Steel Legend supports AMD XFire, meaning you can link multiple identical gpu models(2x RX 580s, for example) for extra performance - but this performance gain varies widely.
The Nvidia version of this is called SLI - again, the models must be identical, and it doesn't matter what the brand is.

Are you trying to SLI on a XFire only mobo? Well, even if that were the case, you have 2 different cards...

It is possible to run both cards unlinked, but there's no real reason to do that.
So why do you need to run both a 1080 and a 1070?

I'm trying to run the cards unlinked since I just couldn't back in the day anyhow get another 1080. What does this mean, the port is dead, or? Thank you!!

 

[X-87]

PCIe slots:
PCIE1 (PCIe 3.0 x16 slot) is used for PCI Express x16 lane width graphics cards.
PCIE4 (PCIe 3.0 x16 slot) is used for PCI Express x4 lane width graphics cards.
* If M2_1 is occupied, PCIE4 will be disabled.

I tried putting my SSD (Win10 boot) to other port on the mobo, didn't do anything.

 

[Phaaze88]

I'm trying to run the cards unlinked...

But... why?

What does this mean, the port is dead?

Since you already tried running your gpus in the 2nd slot alone and nothing happened, it's quite likely.

 

[X-87]

[QUOTE="Since you already tried running your gpus in the 2nd slot alone and nothing happened, it's quite likely.
[/QUOTE]

Well this problem got solved easily, it was the M2_1 port that if its occupied, it will disable the other PCIe x4 port for some random reason.

Got a total different problem now, the computer keeps restarting without any notice, sometimes less than 2 minutes from the boot and sometimes even 2 hours. Sometimes the screens freeze and it turns off, or the screen turn off and so does the PC and it'll boot again.

 

[Phaaze88]

That usually points to a power supply problem...
This happens with both GTX 1080s installed? Does it happen with only one?

 

[deepfabry]

Got a total different problem now, the computer keeps restarting without any notice, sometimes less than 2 minutes from the boot and sometimes even 2 hours. Sometimes the screens freeze and it turns off, or the screen turn off and so does the PC and it'll boot again.

but now except for reboots can you play correctly in sli mode ?

as already said it could be a feeding problem given the addition of a second card...

 

[X-87]

That usually points to a power supply problem...
This happens with both GTX 1080s installed? Does it happen with only one?

I don't have 2x 1080's but 1080 (not OC) and 1070 (OC).
I have 750W psu but the problem was I had my ram speed too high set from the bios, heh.
Had to run 3000MHz on 3200MHz ram but I guess it isn't that big of a deal.

 

[X-87]

but now except for reboots can you play correctly in sli mode ?

as already said it could be a feeding problem given the addition of a second card...

I probably didn't understand but I don't have a sli bridge or so, because the cards aren't identical anyhow by specs so I'd not rather take a risk destroying one when I've heard bad stories from using two different specd cards on sli. So I don't play(?) on sli mode. It was just motherboard "design" to use the other m2 port instead so the 2nd port for gpu will be enabled again or so.