my 4870x2 is working now yeh, coz i had it replaced ha. I can confirm that the stuttering and shadow flickering is still there even with everything not overclocked, even downclocked. So my original theory that the overclock put too much strain on psu is out the window. I'm guessing I may need a clean install, I've had my 1900xtx and gtx 260 put into the phenom rig before i put the 4870x2 in it. If that doesnt fix it, then it may well be related to the PSU. But surely 20A x 4, using 3 seperate cables to power the card is enough. I doubt I will be unlucky enough to have another faulty gpu The 4870x2 scored about 14k in 3dmark vantage, which is kind of normal. PRoblem is the stuttering and shadow problem is appearing in most games. Not happening in source games i've got on steam. happens on crysis, and mount & Blade. Don't have many more games installed atm to test. Another odd thing i've noticed is, compared to when I had the gtx 260 in, the mouse appears to take much longer swipe for a 180 in all the fps games ive tried. however the mouse accelration feels the same, if not faster.