Can't get full resolution in Surround

[mikemayday]

Hello,
Some time ago I've tested triple wide Surround on the following setup and it worked like a charm:
GTX 780
One Dell 2209wa 1680x1050 (native) connected by DVI->DVI
Another Dell 2209wa 1680x1050 (native) connected by DVI->DVI
One cheap Asus monitor (I think it was a VS228DE native 1920x1080) running 1680x1050 connected by HDMI->DVI cable
Sadly I don't remember the drivers I was using then.

I was able to run the desired 5040x1050 @60Hz without a problem.

My new setup isn't working correctly.
GTX 1070
One Dell 2209wa 1680x1050 (native) connected by DVI->DVI
Another Dell 2209wa 1680x1050 (native) connected by HDMI->DVI
One Dell p2212H native 1920x1080 running 1680x1050 connected using a DP->DVI passive adapter and DVI->DVI cable
Using the latest drivers

The monitors work fine until I enable surround. When that happens, I can only choose a maximum resolution of 3840x1024. For some reason it's defaulting to 75Hz but I CAN choose 60Hz.

What am I doing wrong? Is it because of the passive adapter? Does it HAVE to be active, even in a new card like this? Would a DP->DVI cable work instead? Am I shit out of luck until I get a monitor with DP input?

[scavvenjahh]

Digital is digital; Surround works with DVI monitors no problem. Since your monitors work fine in extended mode, the adapter may not be the culprit anyway. That being said a DP->DVI cable would be a more elegant solution, and an easy way to be sure as well. You needn't worry about active adapters - it was only a requirement for early Eyefinity.

[mikemayday]

Thanks!
As it turns out, the culprit was the p2212H monitor - it had a different sync polarity than the other Dells. Switching back to the previous Acer (not Asus...) fixed the problem. I'm gonna buy a cheap used 2209wa and that should be the end of it.