MSI P6N Platinum!? I am Going CRAZY! Please Help!!

Ok here it is.. I have a MSI Platinum P6N MOBO, along with Nvidia 285 GTX, 4gb's ram, 160 gb IDE, 500 gb sata, cpu is Q6600 quad core, Power supply of 750watts, and I am running windows 7. I have had run this same system with multiple video cards including 8600 512mb geforce, 9600 gt, 9800 gtx, and now I am running the BFG GTX 285. Every single time I try to play a video game that requires a pretty good graphics card I get skipping and freezing; this includes such games as, GTA4, Bionic Commando, Prince of Persia, even Disneys Bolt. I just got my 285 gtx and I thought for sure I wouldn't have a problem playing GTA4 and wham, it started freezing almost instantly. I've tried changing driver for my video card and that didn't work. I've tried blasting the mobo and peripherals with a giant fan to cool it down, no worky. I've been trying to oc but I don't feel like I' am very good at that so I am not sure if that is the problem. right now I am oc my cpu at 3.15, when it is normally at 2.40ghz. I've tried to play these games with and without OC'ing to no avail.

This is the first time I am asking for help on this issue. I really think with the components that I have I should be able to play these games resonably fast without a hitch. Also I am running Win7 in 32 bit. IF someone can please help me to solve this problem, I feel like I have wasted so much money on all this hardware and it doesn't work like it should. The reason I put this in Mobo general is because I have a feeling that the problem lies somewhere within this motherboard, is something wrong with it? Thanks George

I have formated the pc about 4 times since. I just put windows 7 in 2 weeks ago. Before that I had a a different win7 that I put in a few months ago. I do a clean install of about every 2-3 months.

OK redgarl, I'll try that but remember, I've had the same problems with 3 video cards before this one that I just got 2 days ago. The monitor I am using is a 26" acer with 1920x1200. I was overclocking my cpu through my bios but have since stopped because I really didn't know what I was doing. I was just following a guide I found on the web. I figured that I may be overheating my system by doing that, but i've never really had any problems overclocking, plus I was getting my cpu up to 3.15ghz but I never saw any difference when gaming between my normal 2.40ghz and the overclocked one..

Plus I've heard on a couple sites that my MOBO does not work well with Quad cpu's. When I check my cpu usage after or while playing a game, its 4 cores are usually maxed out completely.

Ok so I am at a loss here. Does anyone else know or thinks they may know what I should do here? Is it my mobo or something else? Is there some sort of diagnostic I can run to determine the problem?