Appreciate the help & advice guys
This is what ive now done
1. Replaced Power supply
2. Changed heatsink/fan on CPU
3. Removed 1xDVDROM and 1X80GB HD (so power sonsumption is lower
4. Unplugged/Re-plugged all cables & memory
PC seems more stable and hasn't rebooted yet after 4hrs online
I'll keep you posted
thx again
