Server 2003 Unexpected Shutdown

Hello all,

I recently been having some troubel with my dell server. When I come in to the office in the morning, some days the server will be off (its never supposed to be off). I have been checking the system event logs, but there is no helpful information as to why. All I get is :
Event Type: Error
Event Source: EventLog
Event Category: None
Event ID: 6008
Date: 5/10/2010
Time: 8:00:53 AM
User: N/A
Computer: SERVER
Description:
The previous system shutdown at 9:31:28 PM on 5/8/2010 was unexpected.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: da 07 05 00 06 00 08 00 Ú.......
0008: 15 00 1f 00 1c 00 c9 02 ......É.
0010: da 07 05 00 00 00 09 00 Ú.......
0018: 01 00 1f 00 1c 00 c9 02 ......É.

Nothing else. The server is connected to a UPS that seems to be in a working state (no error or service lights are activated). If there is one common theme in the event log is that an event 12517 & event 12503 usually occur before the unexpected shutdown, but I read online that these are harmless. Please help me out with any info or maybe direct me in a good direction to look. Thanks for any help in advanced.

FYI: I am running SBS server 2003 SP2.

The only fix that I have found so far, is to run Citrix on a Compaq server. It might be also possible that the dell motherboard would be dying or some other system might be broken. Otherswise you would want to try to reinstall OS again and check whether that works or not.