two 6870s, -v crashes the computer into restart

[Houseonfire]

I have two 6870 cards, and when I enable -v as the flag on both of them, it crashes the computer and restarts the system.
 I can run -v on one card at a time only. The problem is, if I don't enable it, I lose 100m/hash on the card that it isn't enabled on.

Is there any way around this?


edit:
I have the latest ATI drivers, and the latest AMD APP SDK drivers.

[RyNinDaCleM]

Sounds like you're using GUIminer...
Try CGminer here!

It's much more efficient, and may fix the problem.
Something else to check, you crossfire disabled?