ati radeon hd3850 problem - ideas? suggestions?

so heres the story;

i have a core 2 duo 2.4ghz with 2 gigs of ram etc etc(im not sure how specific i need to be). i previously had a nvidia 8500 gt, and decided to upgrade so i got a hd3850 512mb. since then, i have had difficulties. now ill try to play crysis, and after the level loads and i "press any key", i can run around for about 5 seconds, then it gets choppy, then crashes. the same thing happens in bioshock, and kayne & lynch similarly freaked out about 40mins into a level and i cant even start mass effect. however, for some reason deadspace works, as does supreme commander and some older games.

has anyone heard of anything like this before, or have any ideas as to what i should do? i have all the lates drivers, patches etc, i've done the whole uninstall+driver cleaner in safe mode+reinstall thing and am rather miffed.

By the looks of things it sound like some of your old card driver is not intirely removed. It could be best to remove your drivers ati entirely,

reboot your computer...let windows detect your card and lead it straight to your driver disc. Then install the rest.

And do not forget to update directx too.

Had similar problem before and it did the trick for me.

Hope it helps.

download a program called driver sweeper (free), boot into safe mode, run the program and delete any nvidia drivers (if you havnt already), reboot and install latest ATI drivers.

Also try setting the fan speed to 60% or so, those 3850's can run pretty hot which can cause some disturbance