Nvidia Surround Left Monitor becomes distorted after enabling Surround

[Erk1209]

Hey all,

I just set up a triple monitor set-up powered by dual GTX 680s. I have them connected by three DVI cables, two in the top card and one DVI in the second card. The monitors are 3x Samsung s23a700d at 120Hz. To preface my questions, all three monitors are connected by dual link DVI and when not in surround mode each displays at 1920x1080p at 120Hz without any issues or extra effort on my part. This is using Nvidia's latest 306 drivers that just came out a week or so ago.

Here is my issue:

As soon as I enable surround in the Nvidia control panel the left monitor displays at a much lower resoluton than the other two and the whole set-up reverts to 60Hz. The only way I can correct this is to go into the Windows displays settings, reduce the overall resolution and then move it back up to the native 5670x1080p. At this point all three monitors look perfect, but at 60Hz. Going back into the Nvidia control panel and enabling 120Hz results in the left most monitor again dropping to a lower resolution. I can correct this again by reducing the resolution in Windows and then moving it back up to 5670x1080.

Has anyone heard of this before? It isn't deal breaking but if the current settings don't hold it will be annoying to constantly change things around.

[Delphium]

I almost sounds like the left monitor is connected to a SL-DVI output, which would be limited to 1920x1200@60hz, but you say it does run at 1920x1080@120hz when its running in extended mode.
Could you possibly just recheck the refresh on that monitor when its in extended mode, it is very strange that it would run at full 120hz when in extended mode and not when in surround mode.

You say you have dual 680's, which ports on the gpu's are the monitors connected to?

[Erk1209]

The monitors are connected to the DVI-I and DVI-D ports on the top card and the DVI-I port on the bottom card. Here is an update including what I've tried since my first post

"To update this:

I have attempted to reinstall Windows, have tried every Nvidia driver available, shuffled around monitors and cards, tried using an active display port to dual link DVI adapter and have come to this conclusion:

I can run any two screens at 120Hz but the moment I enable the 3rd, the left monitor has extreme distortion.

In surround at 60Hz the displays look perfect but as soon as I move to 120Hz, the left monitor has problems again.

With the left monitor distorted, i.e. at 120Hz surround, if I launch a game like Borderlands 2 the game will run at 120Hz with zero distortion or issues. I know because I'm running vsync and fraps shows me above 75fps frequently.

If I drop back to Windows, the distortion on the left monitor resumes.

I contacted EVGA and they told me that what I was doing and the way I was doing it was officially supported but had no other answers for me.

If anyone has any answers or suggestions I would appreciate it. Or if any more details would help someone else unravel this mystery I'm happy to provide them"

Thanks in advance for your further assistance!

[Paradigm Shifter]

I thought that one of the DVI ports on the 680s was single-link, while one was dual. Although Anandtech says that both are dual-link, so I'm not sure where I read that. I believe the HDMI port is 1.4, and therefore should support 120Hz 1080p. An HDMI->DVI cable might be a fix...

edit: Also, if you're running bezel correction, since moving to any driver newer than 301.10, I get serious distortion on the desktop when coming out of any full screen game and returning to a non-bezel correction resolution. Only disabling bezel correction completely in the drivers setup solves the issue.

[tancients]

Yeah, EVGA will chalk it up to drivers and leave it at that in most of these cases.

Since having all 3 connected at the same time, but not in surround, generates 120hz 1920x1080, I'd try re-checking cables.

I also recently came across a post in another forum that shows the actual optimal monitor setup is to have the surround setup order the monitors as 1, 2, 3 due to how the load gets distributed on the X/Y plane.

My current setup is using different monitors (the BenQ 120hz), so I can't provide suggestions that worked for me, such as using displayport to support 3d. Nvidia states they won't do 3d over hdmi.

Have you also tried switching monitor locations? And using different DVI cables between each monitor? It seems extremely strange that it is always the leftmost monitor at all times regardless of setup. Also try rolling back to an earlier nvidia driver version. The most recent ones have a few issues on various configurations. One of the 301.XX is probably one of the more stable ones since you have a more standardized setup.


You can also use moninfo to check the polarity of each of the monitors and see if one is reading strangely for whatever reason.

[Paradigm Shifter]

No 3D over HDMI?

Ouch. :(

[tancients]

No 3D over HDMI?

Ouch. :(

It wasn't until very recently that you could do nvidia 3d vison over displayport. You used to need a $100 adapter to convert it to DVI.-DL. There aren't many 120hz monitors that do 1.4a displayport and work well with 3d vision though.

I thought I read that it was a technical limitation based on how 3d vision works, but I do not know the details off the top of my head.

[Wijkert]

I also recently came across a post in another forum that shows the actual optimal monitor setup is to have the surround setup order the monitors as 1, 2, 3 due to how the load gets distributed on the X/Y plane.

Can you post a link to the thread you are revering to?

@OP is the left monitor connected to the second 680?

[tancients]

[quote]I also recently came across a post in another forum that shows the actual optimal monitor setup is to have the surround setup order the monitors as 1, 2, 3 due to how the load gets distributed on the X/Y plane.

Can you post a link to the thread you are revering to?


http://www.overclock.net/t/1286187/nvidia-surround-users-please-check

"Please confirm this someone- but like i said in my last post- its the way your cpu divides up the tasks to tell the gpus what to do. It has to be sequential for the way the code is written to be optimised. If you can imagine a grid that starts out at (x,y) in the bottom left origin 0,0 and extends to however big your display resolution is, your cpus schedule the task of 3 monitors by dividing that whole image into 3 pieces. It has to compute that image along the x axis for every pixel and if your not going in sequence with your monitors your cpu has to add an instruction to exclude the middle part until after the third part"

[Wijkert]

If I understand this correctly this only matters when running SLI. A single card setup shouldn't be effected. May do some testing though.

EDIT: even though it was highly unlikely that the way monitors are connected would impact performance on a single card, I tested it anyway. Below are 3dmark11 performance scores:

DVI1 – DP – DVI2: 10681
DVI1 – DVI2 – HDMI: 10683
DVI2 – DVI1 – HDMI: 10685

The scores speak for themselves. There is no performance difference measurable. Will be using the top config, since that way both my Xbox360(VGA) and my PS3(DVI) can be connected to the middle monitor as well.

[Paradigm Shifter]

I've been playing with GTX670 4GB SLI today, and with 306.97 drivers I have issues with the monitor on the second card squashing the output if transition between resolutions isn't 'proper' (eg: a game crashes).

I'm wondering if the latest drivers have so interesting bugs...

Haven't found a fix or workaround, but hoping that nVidia will fix it in a new driver. :/

[Wijkert]

I've been playing with GTX670 4GB SLI today, and with 306.97 drivers I have issues with the monitor on the second card squashing the output if transition between resolutions isn't 'proper' (eg: a game crashes).

I'm wondering if the latest drivers have so interesting bugs...

Haven't found a fix or workaround, but hoping that nVidia will fix it in a new driver. :/

Use the same driver, but haven't experienced the same problem. What happens when you disable SLI?

[Paradigm Shifter]

Same thing.

It's on the monitor on the second GPU which does it - if I swap monitors around, whichever is on the second GPU on occasion, is vertically squashed. It's fixable, but slightly annoying. ;)