Ashley, Tricky - but as already has been pointed out I would look at memory first (memtest86+), though if it was a proper server, it should have ECC memory which should minimise this risk . Power would be net on the list - some systems have voltage monitoring you can look at - other wise voltmeter looking for +/-5V, +/- 12V and +3.3V on the ATX connector.
Regards, Martin -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html