Vista 64 or something else

So a couple of days ago i was using my comp and i got off for a few after like 10 mins the monitor powers down and will come back when on by hitting a key or movin mouse but this time it wouldnt come back, it kept sayin no signal so after a couple of restarts i couldnt get it to come back on so i decided to do a quick formate of my c drive and it worked at first but then when i would powere up i would have the boot screen then when it went from the vista loading screen to the desktop i would lose signal and have to turn monitor off then back on and it would work. Then after dlin all of the drivers for my gpu and mobo it would only let me cahnge my resolution to 1024 by 768 and i no for a fact my monitor can support better. Also b4 the reformate my monitor would be named when i would go to personalize desktop but now it just says generic non pnp with 9800gtx and i cant install the drivers for my monitor cause it says that they cant be automatically installed so it says to manualy update them and when i do that vista tells me that the drivers are up to date. Also when ever the monitor flashes or flickers when installin something i lose signal and have to turn monitor off then back on and sometimes i have to do this more the once b4 i get the screen back. Im using vista 64 with sp1 and my monitor is a viewsonic 2235wm and my gpu is 9800gtx. Any help would be appreitated cause im startin to lose my patients with this comp.

I forgot to add that if i uninstall the graphic drivers i can change my resolution to whatever i want, its just when i install the drivers it takes away all resolutions but 800 by 600, 960 and 600 and 1024 by 768