i'm running a p4 3ghz 800mhz fsb 1mb cache

Ati radeon x600xt pci-e graphics card-with a new huge artic cooler fan (old one started screaming)

2 sata hard drives one 160 one 300

at the moment running a normal cd-r drive but have a dvd-r drive ready to go in too (psu doesnt have the new style ata power leads)

the motherbourd and ram mentioned above.

running windows xp pro

it did install and run windows ok, was a little sluggish but came up with the odd error which i at first put down to the windows disc i used (bro rebuilt it with sp2 added) but it did run and i did manage to install all drivers and programs and run windows update which after installing all killed exploerer as it would crash on start up leaving me with just the desktop to play with
all this with it crashing randomly also.

i'm pretty sure it is the psu as the mbourd manual says what can happen with a 20pin connector but its just where it said "cpu unworkable" thats giving me second thoughts. it came up where the cmos lists your hardware in dos at start up, but after going into bios and resaving them it would boot up normally until the next crash.

I'd rather go for a 600w+ psu but it also needs to be 24 and 8 pin power connector (alot of them are 20) i was originally looking at hyper ones but didn't fancy the £80 price tag but if it comes to it i'll have to spend the extra.