Help me I'm going crazy?

Ok this is my second system build.

I have and ASUS PQ5 pro with 4 gb Cosaire dominator 1066 DDR2. Intel Core Duo E8500 with a NVIDIA 9800gt graphics card. Windows vista 32bit installed from a previous build on and SATA hard drive. 1 DVD rw blah blah blah. I installed a raidmax 730 w power supply because I initially thought that that was the problem. However the previous 500w PSU shoul have been fine. (but the new ones is neater)

Any how upon initial boot (with the 500w power supply) computer came on fine. I loaded drivers ect restarted several times updated bios. started playing games and you know how it goes in the middle of a 25-man raid the dam machine goes "click" and shuts down completly.

So I reseat the entire system (including the processor) resec the cmos and the system boots. then same thing click and the system shuts down.

At this point I reseat the memory and and reset the cmos again and "jack with the guts abit " and it works. This time it freezez for no reason. no gaming going on .

I decided after some reading that maybe the 4 pin psu to the mobo needs to be 8 pin to complement the mobo 8 pin connector. so I buy the new powedr supply and again reset the cmos and reseat the memort. System boots.

At the suggestion of some previous poasters I ran prime95 for about 20 minutes and got nothing..no errors.

then I ran the vista system rater and the computer locks up and wont boot. the bios were reading temps for the mobo at 91 and the cpu at 104 ...thats degrese Farenheight.

Suggestions ?

run memtest86+ to check the ram

ok so if my system wont boot ......and only boots when I jack with it ....how do I get windows to reinstall?

also voltage is set in the bios ?

also why would a poor install of windows caust the system not to boot to the bios?

So I booted with one stick of memory. computer was stable fo 3 days and passed prime 95.....sent the "bad stick" back and got 2 in return ....what a deal....turnes out one of the 2 GB sticks of cosair dominator memory was bad :-(