4850 Everything Choppy including Desktop

I"m having a huge problem with my Asus HD4850, Everything is extremely choppy. When i move windows around they are really choppy, there is screen tearing and blank screen beihind the windows I move around and my CPU goes up to 25%....(100% of one of my cores) it basically seems like I have no driver installed.

However, I've tried so many drivers, i've used driver sweeper and driver cleaner pro (on separate times) trying to install the drivers cleanly, I cannot figure out what is wrong. I feel like it has to be the drivers but im just not sure.

I've taken the card out of the computer and put it back in. All my temps are fine, but videos games and just moving windows around is visually terrible. Reformatting is my next option but thats really going to be a problem for me atm.

I have a project I need to edit with AVID this weekend and video looks so terrible its almost impossible to edit anything.

If anyone has any idea, I would be forever Grateful, im going nuts right now.

have you tried another card in the machine? It may be a memory/motherboard issue.

Hey, im running windows XP Pro, I have tried My old 8800GTS with the new Nvidia Drivers and it does the same thing now. SO I reformatted last night and installed the drivers again and Nothing, same thing. When i Move windows around the edges are still all choppy and there is a quick redraw of the windows behind windows I move. It seems almost as if my drivers haven't been installed at all...however I know thats not true, it plays games fine and i've tried too many drivers for that not to be true. Maybe Motherboard issue? thats all i can think of. BTW my mobo is a gigabyte p35-s3L - and Updated the Bios not too long ago - and downloaded the newest chipset driver when I reinstalled windows last night.

Yea theres no dust, and all the fans are running (one fan in the front one in the back and a huge aftermarket HSF for my Proc, Cpu is 34/28/34/28 at idle...power supply is 600Watt SLI Cooler Master I believe...i have another PSU maybe i'll try that just to make sure, its actually not as good as the one I have in there tho.

I went away for the night right after I reformated and i hoped that when I reinstalled AVID the video would at least be a little better but thats not true at all...it might even be worse....