ComputerBB

I recently upgraded most of my hardware in order to play some of the newer games on the market (HL2, Doom3) and i have a bit of a hang up that i have read endlessly about to no availe. I'll post my spec's as i go.

When i am web surfing or browsing my files or listening to music, everything seems to be fine (for the most part). When i start gaming, i get issues. Within 15 minutes my performance degrades and my screen goes black, then i get an error, usually related to the video card driver. Sometimes my system randomly reboots and then some of those times it goes to the bios and gives me a message about the cmos settings being wrong. I typically load defaults and then renter the bios too disable the onboard sound (turned back on by default). I think these problems are related to overheating or an insufficient psu.

The hardware: All brand new stuff
My cpu is a P4 2.8 ghz with 800 mhz fsb, Hyperthreading
My mobo is a MSI 865 PE Neo-2 platinum edition
My ram 1gig 400 mhz, 2 sticks of 512 I don't know the brand
My gpu ATI Radeon 9800 pro 128mg ram
My psu L&C 400W
My os Windows xp with sp2 and all critical updates
My drivers and chipset are the most current

When i do dxdiag tests, everything passes with flying colors. Also, device manager shows my hardware configured properly.

I suspect overheat or insufficient psu for a couple reasons.
The L&C 400W psu was 40$ US and from what i've read, a cheap psu will cause tons of problems and a good brand of the same wattage would cost between 60$ and 100$
The mobo has a program to moniter fan speeds, temps, and voltage.
When gaming, my cpu temp would jump to about 65-70c in minutes.
The voltage on the 12v rail will be like 12.77 and 5.8 on the 5v rail and 3.34 on the 3.3 rail.

I also only have 1 case fan and then the stock fans on the psu and gpu. Also stock fan and heatsink for the cpu that came with it.

Any ideas?

I would first test the system ram, to do this download "memtest86", can be found on google, and run a full diagnostic, if everything checks out fine then I would get either an Antec or Enermax PSU.

that is a hot CPU

When gaming, my cpu temp would jump to about 65-70c in minutes

That is extremely warm for an Intel cpu. My brother-in-law has the exact same cpu and his runs at about 43*c while gaming. He isn't using the OEM heatsink and fan, but that is still an enormus difference in temps.

Ya might wanna check to make sure all your timings (Ram and CPU) are correct in the BIOS.. something sounds farked up to me.