I know that vram is not additive with Xfire or SLI. As in having 2 video cards with 2GB of vram does not give you 4GB.
What I don't know though is this. If I have 2 models of the same card but different versions how does the vram work.
For example: If I have a 4GB version of a card that feeds to the monitor and a 2GB version of the same model that is linked with crossfire/SLI. Does this mean the game is now limited to using 2GB or does it still have 4GB available.
Actually could someone just explain how Xfire/SLI work please :)