Problem enabling Nvidia surround (2D) with non-identical displays

[Duff-Man]

Okay, I have three 30" screens that I'm trying to get to work together using nvidia surround (2D mode), with a pair of GTX480s in SLI.

The screens are an HP ZR30W, and two Hazro HZ30Wi. All three screens work fine independently, or together in windows using the "activate all displays" option in the "configure SLI, PhysX, Surround" option in the nvidia control panel. However, when I try to enable nvidia surround, either one or two of the displays has a red cross next to it, saying "Replace with a different display, all surround displays must support a common resolution, refresh rate and sync polarity".

If I have the HP in the primary GPU socket (the left hand DVI input from the top card), then that one is green and the two Hazro are red. If I put one of the Hazros in that socket, then the two Hazro are green and the HP is red.

The obvious conclusion is that the screens need to be identical in order for surround to work... But this is not the case for 2D surround, only for 3D! There are plenty of people who have got 2D surround working with different displays (even ones that don't have the same native resolution, so long as they run at a resolution and refresh rate that all screens can handle.

Anyway... I tried creating a custom resolution for each screen, using manual timings and the exact same polarity (tried both positive and negative). Each of the screens passes the test and enables the identical custom resolution, but still, no luck - I still get the same message when I try to enable surround.

Does anyone have any suggestions for anything else I can try? I spent a lot on this hardware and did my homework first, so it seems a pity not to be able to get it going for its intended purpose... Thanks!

 

[Duff-Man]

Thanks for the link rickh That looks like a very promising thing to try... I'll have a crack tonight and report back.


Ezyryder: I did consider posting this in the graphics card section, but anticipated a rapid fanboy-related thread derailment ("lol Nvidia driver fail", "stfu catalyst is more unstable" etc).

 

[Duff-Man]

Okay, I tried editing the EDID info, and things seem to have gone pear shaped On the plus side, I found the reason why the original setup didn't work: The Hazro screens have a (+)horizontal, (+)vertical sync polarity, whereas the HP has (+)horizontal, (-)vertical.

Anyway, since everything else is compatible I opened the EDID file with moninfo, saved as a .dat file, opened with phoenix, and changed the sync polarity to match the Hazros (+)H/(+)V, leaving everything else the same. I saved it as a .inf file, and used this to update the driver.

Unfortunately, it seems the HP screen would not accept this... When I enabled the new driver the screen stopped taking an input I needed to power off the screen for 30s before I could use it again.

Anyway, this leaves me with one question: Is it inevitable that changing the sync polarity of a screen will stop it from working? is this something which simply can't be adjusted? If it can't be changed, I guess that there is no way to get a triple-screen setup running with these monitors (eyefinity or nvidia surround)


Any help would be very much appreciated!

 

[Duff-Man]

Good point about trying an un-modified .inf, I'll give that a go.

As for switching the polarity of the Hazro... Well, I considered it, but after I modified the HP and it wouldn't even show up in windows or activate in POST, I got a bit concerned. The HP "came back from the dead" but who's to say how the Hazros will react? Anyway I figured I would find out if it's even possible to switch the sync polarity first, but there is just so little info around on the web - I still don't really have a clue what the damn thing is! For all I know it could be something that's fixed in hardware...

Searching for "monitor sync polarity" or similar just brings up other threads from people having trouble with nvidia surround