Random BSOD Errors

[mysticsniper]

In the last few weeks I have started to get lods of BSOD's and stop start errors. the faults appears at random, and there is nothing consistant. I first got the errors when being online, but now I get them more when playing games. The first bsod came with this error message:

"STOP: 0x0000009C (0x00000004, 0x00000000, 0xb2000000, 0x00020151)
"MACHINE_CHECK_EXCEPTION"

The next ones error message I keep getting is:

"The STOP error is 0x00000050: PAGE_FAULT_IN_NONPAGED_AREA"

I've run diagnostic checks on everything that I can and it all seems to be working normally as far as I can tell. Memtest reports no errors, No hdd errors either. I am not overclocking anything, temps are fine, I don't have any viruses, spyware is sorted everyday.

Any idea's

TIA

My system spec's

A64 4000+ San Diego
DFI LanParty UT NF4 Ultra-D 2006/04/06
OCZ 1GB PC4800 Dual Channel Platinum EE EL-DDR (2.5,3,3,7)
Connect3D ATI Radeon X1950 XT 256MB GDDR3
Samsung SM-930BF 19" LCD Monitor
2x WD Raptor 74GB
Audigy 4 Pro
Pioneer 110DBK
Pioneer 109XL
CM Stacker Case
Antec NeoPower 480w
Logitech Z-5500 Speakers
Logitech Cordless G7 Gaming-Grade Mouse
Logitech G15 Keyboard

 

[sja360]

try reseating the graphics card and any other pci/pci-e card. also if that doesnt work try going one by one removing each card.

 

[FrostedNipple]

might be your ram!, i used to get thos sort of errors when i had bad ram, check your ram, it could have bad sectors

 

[mysticsniper]

Am thinking that it could be my PSU. It is about over 2 years old, and how could I test to see if that is my problem