Just put together a system with 3 Dell U2711 monitors and 2 Sapphire HD 6950 2Gb video cards in crossfire and I cannot get the maximum published resolution working.
Asus X58 chipset mainboard, i7 960 CPU, 12Gb DDR3 ram running Win7 64bit
U2711 max resolution is 2650x1440, so Eyefinity should support 7680x1440, however best I am getting is 4800x1200.
Disabling Eyefinity gives me 2 monitors at max resolution of 2650x1400 and the other will only go to 1920x1080.
Troubleshooting tried so far
I am connecting 2 monitors with DVI-DL cables and 1 with displayport (U2711 has DP input).
I have tried swapping monitors and cables with spares - the issue doesn't stick with any one specific monitor so have ruled them out as creating the problem. Also doesn't seem to stick with any one DVI cable. However the prolem display always seems to be the one on the bottom DVI slot on the video card...though not sure if this is significant or not...?
I am using the latest ATI drivers - there are no drivers for the U2711 (wish there were though - Windows just reports it as a generic PNP monitor).
Would love to get his resolved as I have laid out quite a bit of cash on the setup and the 4800x1200 just looks really underwhelming
Just found out the Sapphire HD 6950 2Gb Dirt3 edition has one DVI-DL and one DVI-SL. The issue was the DVI-SL is limited to 1920x1200 thus preventing the monitor going to 2560x1440 (DVI specs at wikipedia).
Traded them in for two Sapphire HD 6970 2Gb cards with two mini-DP and one DVI-DL port - all good now!
Now if I could only select my post as best answer....