I have tried not installing CCC and i still get the issue, i can get it on the desktop with an "unstable" CPU/ mem overclock by running linx or prime 95, it deff seems like it is a driver issue that is for sure, exactly what no one really knows yet, BUT, it dose seem it isn't just on 64 bit OS's or JUST win 7 for that matter, so it would kinda indicate something is off that is common amongst ALL the driver versions, so to me one would think that ATI would b RUSHING to get a fix out for this....then again they have no competition atm so there cards r selling, so they might not even care till Nvid announces there new Dx11 cards (and that would just suck and IMO b poor business practice) also i can throw an old x1950pro in the same slot as my 5770 and have no problems with locking or lines so it IS specific to the 5xxx series of cards

Also on a side note this 5770 would also line/lock-up in my 939 rig on an old DFI NF4 mobo and windows XP (it almost seemed worse on that then on my AM3 rig)

So im curious what do the card manufacture's say when you say that you HAVE tried the card on different machines and os's with the same EXACT problem? do they offer to RMA your card or what happens there?

Dragon