Bad 2D Surround Performance with 2x GTX690

[wildem]

Hi all....hoping someone may have some advise.

I just put together a new system...as below...

Intel(R) Core(TM) i7-3930K CPU @ 3.20GHz
Asus RAMPAGE IV EXTREME
Gskill 16G DDR3 2400
2x Palit GeForce GTX 690
OCZ-AGILITY3 (120GB, SATA600, SSD, NCQ) : 112GB
Corsair Force GS (240GB, SATA600, NCQ) : 224GB

Thermaltake Toughpower TP1200


Microsoft Windows 7 Ultimate 6.01.7601 (Service Pack 1)
Platform Compliance : x64


My problem lies with performance once I setup 2D surround mode on 3x Samsung 27' SA950 monitors USING BOTH CARDS.

What i mean is that when using only one graphics card, games running in surround mode at 5760x1080 run at a constant 50-80 FPS.

Once I setup both cards QUAD SLI in surround mode at same resolutions and settings....frame rates drop to around 22 and the sound stutters. Noticeable small pauses and lag when playing.

I am failing to understand why, or how to solve.

Any ideas??

Thanks in advance.

 

[LigTasm]

Driver version? Have you tested both cards in both slots? Bad SLI bridge?

 

[wildem]

Yes, same symptoms regardless of which card used solo. Plus switched in SLI configuration.

Have tried two separate bridge ribbons.

Driver is 304.79

 

[vjcsmoke]

Sounds like the curse of Quad SLI.
This happened to me too when trying QuadFire with 2x dual gpu cards.
It sounds to me like the driver support is either lacking or the particular game you are playing does not properly support Quad SLI.
In that case disable SLI for certain games might be your only recourse.
You might even consider selling one of the 690's and 'downgrading' to Tri-SLI, 690+680.
I'd check Palit's tech support forum and see if they can help you out But I suspect what I outlined above is going to be the case.

I have no idea why video card companies treat their biggest spenders as their lowest priority. Plenty of debugging is done for dual and even tri-SLI, but very little attention is generally paid to potential quad SLI or Crossfire configuration issues.
Monster build btw. Good luck with your issues.

 

[CrazyRob]

Sounds like the curse of Quad SLI.
This happened to me too when trying QuadFire with 2x dual gpu cards.
It sounds to me like the driver support is either lacking or the particular game you are playing does not properly support Quad SLI.
In that case disable SLI for certain games might be your only recourse.
You might even consider selling one of the 690's and 'downgrading' to Tri-SLI, 690+680.
I'd check Palit's tech support forum and see if they can help you out But I suspect what I outlined above is going to be the case.

I have no idea why video card companies treat their biggest spenders as their lowest priority. Plenty of debugging is done for dual and even tri-SLI, but very little attention is generally paid to potential quad SLI or Crossfire configuration issues.
Monster build btw. Good luck with your issues.

Regardless of how this issue is solved, I just wanted to point out, with nvidia, you can't actually sli a dual gpu card with a single gpu card, like you can with ati.

 

[DarkAngel_ZERO]

Sadly, it looks as if NVSurround performance gets incrementally worse the more videocards you add into the mix. I know a lot of people with a standard two-card SLI setup who get higher framerates than a three or four-card setup, myself included. I hope that nVidia figures out the cause of this issue soon.

That aside, here's a few things to try that can help improve performance:
1) Download the ForceEnableGen3 from nVidia to enable PCIe 3 emulation on your motherboard. I did it on my Sabertooth X79 and it really helps the overall performance of the setup.
2)Make sure you're not using any form of MSAA. Since the GTX 690s are limited to 2GB of video memory, you're going to be running out of space fast at 5760x1080 resolutions in a lot of newer games. I've clocked BF3 at 2.45 GB on Caspian, and until recently, Shogun 2 would utilize almost 3.2 GB of video memory.