Dont forget, the res of the monitor is what needs vRam, not size
A 7950 would be great at that resolution for under $500. What problems did you have with your 6950? I think the 7XX series might not be around until late 2013 or early 2014.
I still need to talk with the users that have 1600 screens to see what VRAM usage they are getting in current games. Right now I have some games that will be limited with my 2gb
My issue with the 6950 was not the performance, it was the software and stability. In Windows, CCC caused problems with web browsers showing graphics incorrectly (on my 4850) The solution was to reinstall the drivers without CCC. So my choice was no configuration menu or stability. I was finding that I was getting different stability with GPU overclocks depending on what version of the drivers I was using.
Now if AMD really has made huge improvements on their drivers then I can drop those points for Windows. I'll have to talk with NyxCharon to see how the linux drivers are working.
On nvidias side, I want to use the new features that are in the 6xx series. FXAA and TXAA will be a big help when I can't take the performance hit of higher levels of AA. Same with Adaptive V-Sync.
At this resolution I should be looking for 670/680 4gb SLI or 7950/7970 Crossfire. As I've stated before I don't get to play games enough to make spending $800 or more on GPUs justifiable for me. Although $600 for 7950 Crossfire does seem pretty tempting