Out of the cards you listed go with the 7970's. I run BF3 at 5760x1080 and have a seperate LCD that I use to monitor stats (CPU/GPU Temp, utilization, fan speeds, memory etc..). BF3 at EyeFinity resolutions does use over 2 gigs of Vram. For this reason alone, avoid the 670's unless you go with the 4gb edition. A 7970 is a great card for running high resolutions but wont let you max out games at that resolution even with all its power. For that you'd need crossfire.