Question about r9 390x2 card.

[Shane Spiker]

I was wondering if anyone had any information about setting up 2 r9 390x2 cards in crossfire? specifically what type of benchmarks we could see at 4k gaming.
Thanks in advance.

 

[photonboy]

You do NOT want to use 4xGPU's for gaming in Crossfire or SLI. I'd go no higher than 2x.

- diminishing FPS returns
- not always supported (so uses one GPU only)
- stutter and compatibility issues

Other:
1) If you're talking about the $1500 new card that's overpriced for gaming as it's primarily a VR and software card. It games fine but they (double precision?) features added inflate the price.

2) 4GB per GPU isn't ideal for 4K. Some games are fine but going forward it's likely to be a problem.

3) 4K rarely looks better than 2560x1440 so it's a big waste of money IMO. Due to scaling issues 4xGPU's might give similar FPS at 4K as you'd get with a single GPU at 2560x1440.

(You can game at 2560x1440 on a 4K monitor... not HDTV AFAIK. But as I say below you're limited to 60Hz at 4K so it's not a monitor for high-end gaming.)

Other:
*I strongly suggest waiting for the new cards. AMD Polaris or NVidia Pascal. Rumor has the Polaris 10 card as a little slower than a GTX980Ti but the cost is probably between $350 and $400USD (I saw a $300 estimate which I highly doubt since the manufacturer can set the price and this will be in high demand).

NVidia's offerings may be faster cards but it's still a wait and see. I believe Polaris 11 is a SLOWER card than Polaris 10 (similar to a GTX960?).

Other:
An asynchronous monitor is the cornerstone of the best gaming systems. For that you want either an AMD Freesync or NVidia GSync (GSync is more expensive) monitor. Specs on both should be

- IPS
- 2560x1440 @144Hz (or 3440x1440@100Hz)

Forget 4K monitors as they are currently limited to 60Hz. Add in the minimal quality increase due to pixel count and it's really NOT the way to go. So something like:

a) 2x (Polaris 10, with 8GB VRAM, 90% GTX980Ti perf?), plus
b) 1440p, FreeSync, IPS monitor

I'm guessing that total would be roughly $1500USD.

That's my advice.

 

[Shaun o]

As you know the new range of 390x cards don`t require a crossfire bridge as they now crossfire via the two Pci-e express slots of the motherboard.

Any game that has Mantel support will fair much better with two R9 390x cards in crossfire mode.
You should expect about 55% improvement on frame rates of games if intending to play at 4K resolutions.
With most of the game graphics set to very high or ultra high.

Some games may be limited on frame rate results due to the cpu model or brand you have in your system.
That may effect the final frame rate results.

Each system may differ slightly with that in mind by a few frames per second

 

[photonboy]

http://www.tweaktown.com/tweakipedia/91/amd-radeon-r9-390x-crossfire-4k/index.html

(again, 2X at most. Don't go 3X or 4X)

It's important to understand that articles like this tend to choose the games that support Crossfire or SLI the best. It's hard to get an estimate of how many games don't support it at all, or don't support it properly.

With that said, here's the summary for the link:
"There you have it. Two AMD Radeon R9 390X cards in CrossFire pack a damn impressive punch. We're looking at more than playable performance at 4K, with close to 80-100% scaling in every single game."

The AVERAGE varies a lot depending on what particular games a site chooses to review so you kind of have to average a bunch of averages... sigh. And there is of course what the FPS counter says and what the game FEELS like due to the difference in frame times (a bit of missed frames or stutter can make a supposed 60FPS experience not feel smooth which multi-GPU tends to do).

*I'm not against 2xSLI/Crossfire in general now, but for some games it's best to NOT use more than one GPU if it's not as smooth especially if you don't need a higher FPS.

 

[Shane Spiker]

The card I am speaking about is the powercolor 500$ 16gb of vram. I understand the diminishing returns on using multiple gpu's and not saying this is something i would implement in my system. Just more so looking for information on pushing 4k. at 1000$ for essentially 4 gpu's and 16 gb of ram that comes out cheaper then one titan x card at the moment.

 

[Shane Spiker]

Also I completely agree that some games are simply not supported for crossfire or sli. This is more of looking at future forward.

 

[Vellinious]

The card I am speaking about is the powercolor 500$ 16gb of vram. I understand the diminishing returns on using multiple gpu's and not saying this is something i would implement in my system. Just more so looking for information on pushing 4k. at 1000$ for essentially 4 gpu's and 16 gb of ram that comes out cheaper then one titan x card at the moment.

It's still only 8GB....the memory doesn't stack, even when on the same PCB. It may end up working that way eventually, with DX12, but right now, you get 8GB.

 

[Shane Spiker]

Vellinious That was my fault the card was advertised as 16GB didn't realize that they were just adding the 2 8gb cards together. I was under the impression that the way they set up the cards together they were able to double the video memory.

 

[photonboy]

The card I am speaking about is the powercolor 500$ 16gb of vram. I understand the diminishing returns on using multiple gpu's and not saying this is something i would implement in my system. Just more so looking for information on pushing 4k. at 1000$ for essentially 4 gpu's and 16 gb of ram that comes out cheaper then one titan x card at the moment.

1) x4 GPU's is not ideal as I've said. Spend some time Googling and you'll see it's not recommended.

2) $500 only for that card? I'd look carefully at the build quality (see comments). I'd suggest going with 2x R9-390's instead for $600.

It adds $100 but they should overclock higher, plus if anything goes wrong you still have one card.

3) You know that's a TRIPLE-SLOT card right? Even if you wanted to go with TWO of these (x4 GPU's in total) which I highly, highly do NOT recommend I don't know of many motherboards that would support this.

You'd have to use the top FOUR SLOTS for the first card, and have enough space below that to add a second one. Not likely.

4) Review: http://www.hardocp.com/article/2015/10/19/powercolor_devil_13_dual_core_r9_390_video_card_review/13#.VyGAv2ArL1s

"Two out of six games working flawlessly is not a good track record..."
and
"..We know AMD hardware scales well with XDMA, we just aren't sure how the drivers would handle Quad-GPUs."

 

[Shane Spiker]

Photonboy. Again I completely agree and I fully understand the limitations on hardware that would even be compatible. My question was just inquiring if anyone had heard any information on if a set up like this would be the next ideal solution to pushing 4k especially at the price point.

 

[Gam3r01]

This card would be far from an ideal way to push 4k.
The ideal option is to hold onto whatever money you have until the next generation launches. Many feel Polaris/Pascal will be the generation to make 4k 60FPS viable.
The Devil 13 is a gimmick, dont bother.

 

[photonboy]

Vellinious That was my fault the card was advertised as 16GB didn't realize that they were just adding the 2 8gb cards together. I was under the impression that the way they set up the cards together they were able to double the video memory.

THAT part doesn't really matter as 8GB is going to be plenty per GPU for a LOOONG time. A lot of games are even fine at 4K with 4GB.

I do recommend 8GB per GPU though if possible. As said DX12 supports the option to have both GPU's work on the same frame which not only makes up to 16GB available but also decreases the latency as the frame is created quicker.

(FYI, with 4xGPU's you add a lot of latency since each GPU renders a frame on itself. This also ties into stutter issues but that's a complicated discussion)

Also...
Not that it matters I guess but SYSTEM RAM may help minimize the amount of VRAM required in future games as well. Certain portions of the game may be STREAMED from system memory. I think it's called "shared tiles" or something. There was a demo of zooming into Mars where the textures where several GB's and it was sampled on-the-fly, streamed from system to video memory and played.

That may not get used much, but another feature planned in DX12 is to make the game (engine?) smarter and dynamically move things out of VRAM to system RAM and vice versa during times not needed.

Long story short is that 8GB per GPU should be plenty IMO for 5+ years.

 

[Shane Spiker]

This card would be far from an ideal way to push 4k.
The ideal option is to hold onto whatever money you have until the next generation launches. Many feel Polaris/Pascal will be the generation to make 4k 60FPS viable.
The Devil 13 is a gimmick, dont bother.

That is basically what I came to for a decision I just wasn't sure if I was missing any information that I might have overlooked.

 

[Shane Spiker]

Vellinious That was my fault the card was advertised as 16GB didn't realize that they were just adding the 2 8gb cards together. I was under the impression that the way they set up the cards together they were able to double the video memory.

THAT part doesn't really matter as 8GB is going to be plenty per GPU for a LOOONG time. A lot of games are even fine at 4K with 4GB.

I do recommend 8GB per GPU though if possible. As said DX12 supports the option to have both GPU's work on the same frame which not only makes up to 16GB available but also decreases the latency as the frame is created quicker.

(FYI, with 4xGPU's you add a lot of latency since each GPU renders a frame on itself. This also ties into stutter issues but that's a complicated discussion)

Also...
Not that it matters I guess but SYSTEM RAM may help minimize the amount of VRAM required in future games as well. Certain portions of the game may be STREAMED from system memory. I think it's called "shared tiles" or something. There was a demo of zooming into Mars where the textures where several GB's and it was sampled on-the-fly, streamed from system to video memory and played.

That may not get used much, but another feature planned in DX12 is to make the game (engine?) smarter and dynamically move things out of VRAM to system RAM and vice versa during times not needed.

Long story short is that 8GB per GPU should be plenty IMO for 5+ years.

Excellent point. However my thought is for people say running a triple monitor setup how much does Vram factor into pushing the image? I understand that right now 4 will get most people by pushing on 1 monitor. I wasn't sure if more Vram would be necessary to push to 3 monitors.

 

[photonboy]

One last thing:

The NOISE appears to be pretty high for that card. I'm personally quite sensitive to noise. Anyway, even if it costs a bit more overall my advice is hold off and get:

2xPolaris, or
2xPascal

Both with 8GB per GPU.

(The $500 price concerns me. It's Powercolor and while they may make some okay cards from what I can tell they tend to come in at the low price point by sacrificing the quality of some components like capacitors. I'd be concerned for the life of that card.)

*You may find a single card if GTX980Ti performance or higher is adequate for 1440p gaming which I again recommend versus 4K for reasons I gave above. You may have an adequate monitor as well, so may want to hold off a bit to get a good asynchronous monitor.

GSYNC pricing will hopefully drop but again it's more expensive by $150 or so than Freesync. I can't stress enough that an asynchronous, high refresh (100Hz minimum) is the best thing you can do for gaming.

(Freesync has one MAIN drawback. You do NOT want to buy a monitor that supports 30Hz to 60Hz for example. They need a range of at least 2.5X such as 30Hz to 75Hz or you have problems dropping below 30FPS which is more common than you might think. Anyway, this isn't an issue with GSYNC but both work similarly provided more than 2.5X range.

The REASON is because AMD has to support the low-end via drivers. If you drop to say 29FPS which is below asynch support it then sends the SAME FRAME twice giving you 58FPS. It's still observed as 29 frames but it's smoother and with no screen tearing. That may be CONFUSING, but again just ensure your monitor supports 2.5X or higher for Freesync mode.)

2x980Ti on a 4K 60Hz monitor, vs
1x980Ti on a 1440p 144Hz, GSYNC monitor

Which do you think delivers the best experience?

 

[Shane Spiker]

One last thing:

The NOISE appears to be pretty high for that card. I'm personally quite sensitive to noise. Anyway, even if it costs a bit more overall my advice is hold off and get:

2xPolaris, or
2xPascal

Both with 8GB per GPU.

(The $500 price concerns me. It's Powercolor and while they may make some okay cards from what I can tell they tend to come in at the low price point by sacrificing the quality of some components like capacitors. I'd be concerned for the life of that card.)

*You may find a single card if GTX980Ti performance or higher is adequate for 1440p gaming which I again recommend versus 4K for reasons I gave above. You may have an adequate monitor as well, so may want to hold off a bit to get a good asynchronous monitor.

GSYNC pricing will hopefully drop but again it's more expensive by $150 or so than Freesync. I can't stress enough that an asynchronous, high refresh (100Hz minimum) is the best thing you can do for gaming.

(Freesync has one MAIN drawback. You do NOT want to buy a monitor that supports 30Hz to 60Hz for example. They need a range of at least 2.5X such as 30Hz to 75Hz or you have problems dropping below 30FPS which is more common than you might think. Anyway, this isn't an issue with GSYNC but both work similarly provided more than 2.5X range.

The REASON is because AMD has to support the low-end via drivers. If you drop to say 29FPS which is below asynch support it then sends the SAME FRAME twice giving you 58FPS. It's still observed as 29 frames but it's smoother and with no screen tearing. That may be CONFUSING, but again just ensure your monitor supports 2.5X or higher for Freesync mode.)

2x980Ti on a 4K 60Hz monitor, vs
1x980Ti on a 1440p 144Hz, GSYNC monitor

Which do you think delivers the best experience?

A lot of good points and from my experience I've enjoyed playing with 1 980ti on a 1440p 144hz monitor. I would also agree that it is probably the best solution to hold off on 4k until new cards come out. Thank you for the great information

 

[photonboy]

Final, final thing:

After reading again, I think an original thought was that 4x GPU's would be utilized better IN THE FUTURE, so get now because it's a good deal?

While the answer is almost certainly, YES (used better not the value), it's hard to justify the extra GPU's (four instead of two) not only for the COST in money but the issues which may arise, including Noise. In fact the added HEAT may slow down some games due to GPU throttling.

*The gaming industry is very SLOW to change, in part because game engines, and games have a years-long dev cycle. A small amount of future proofing is fine, but not this, especially if there are negatives.

Save that money, and put it towards a great GSYNC/Freesync (as appropriate to GPU) monitor. I'm holding off for a 3440x1440 IPS 100Hz+ in 2017/18 probably if that's a good res for Star Citizen.