im running 1 8800gtx at the mo and ive got my eye on a freinds faulty gtx,the problem is when the monitor is pluged into the dvi slot the pic is distorted!! if i ran my good card and the faulty one in sli mod useing my good cards dvi,would this work and be ok?
That depends what's wrong with the other GTX - if it's just something in the output stage of the card it'd probably be alright, but if it's within the processing stage you'll have no luck tbh. I'd suggest you just RMA your friends' card if possible.
If you are meaning in games and you are running on a TFT is could be a VSync issue, try turning on VSync to see if that fixes the problem...
run ATI Tool on your distorted computer, if there's errors detected, i suspect it's wrong with the processing stage.