He said he changed to DVI but also said he updated drivers. I think THAT is the real culprit there.
I have a 6970 and have 3 monitors at once, Debrody. One of them is very old and maxes out at 1042x768 resolution, so when I tested it in games I had to limit it to that 768 vertical resolution and "dumb down" the others.
The physical sizes also made it difficult to game that way, because lines didn't match up left to right.
If you have 3 same sized monitors (i.e. 1280x1024) I think you'd have no problems with just 1 of these 6970s. You also have the option to crossfire, adding more power later. That's my intent some time from now, once games get that far ahead in requirements, I'll stick another card in there.
I had to get 2 passive mini-DP adapters, but I grabbed two Apple-brand adapters off of amazon and they work just fine. The third (middle, primary) monitor is DVI.
EDIT: Here's a video of 3-monitor eyefinity testing. All textures and details were maxed, FSAA was at least 4x, aniso was 4x or 8x or so. FPS running FRAPS live was still good.