What kind of video card can I put on this mb

if you mean you want to get another GPU for crossfire, you will need to get another 6770 1GB. you can't crossfire with 2 different cards.

so my mb can handle another 6770?

and have 2gb access right with both crossifired?

You'd think that the VRAM from both cards would add together, but it doesn't. It just uses the power from each one, not the VRAM.

Make sure you're 6770 comes with a crossfire finger to use a crossfire bridge, some do not come equipped with one.

Maybe consider upgrading to a HD 7850 or Nividia GTX 650/660

Best answer selected by edkai.