Gateway laptop turning itself of random

Hello everyone

Heres my issue, worm infected this laptop (gateway MT6728), so I wiped the hard drive, and installed vista (ug) because a pirated version of XP I was using was no longer working, anyways , after reinstalling all my drivers and setting this computer back up , it randomly keeps shutting itself off. At first i thought it was a power issue, but after doing some research i thought it might be due to overheating...anyways it most typically happens while playing world of warcraft. but it can happen even while browsing the internet even with one or two tabs of firefox open...


Went to the event viewer and this is what popped up the past few times, if anyone could help , it would be greatly appreciated

- <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
<Provider Name="EventLog" />
<EventID Qualifiers="32768">6008</EventID>
<Level>2</Level>
<Task>0</Task>
<Keywords>0x80000000000000</Keywords>
<TimeCreated SystemTime="2009-12-07T06:44:40.000Z" />
<EventRecordID>51525</EventRecordID>
<Channel>System</Channel>
<Computer>TheMadHatter-PC</Computer>
<Security />
</System>
- <EventData>
<Data>1:43:28 AM</Data>
<Data>12/7/2009</Data>
<Data />
<Data />
<Data>3003</Data>
<Data />
<Data />
<Binary>D9070C000100070001002B001C005003D9070C000100070006002B001C005003600900003C000000010000006009000000000000B00400000100000008000000</Binary>
</EventData>
</Event>




Also another error appeared ,

"Unable to initialize the security package Kerberos for server side authentication. The data field contains the error number."

with the log of

- <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
<Provider Name="Microsoft-Windows-HttpEvent" Guid="{7b6bc78c-898b-4170-bbf8-1a469ea43fc5}" EventSourceName="HTTP" />
<EventID Qualifiers="49152">15016</EventID>
<Version>0</Version>
<Level>2</Level>
<Task>0</Task>
<Opcode>0</Opcode>
<Keywords>0x80000000000000</Keywords>
<TimeCreated SystemTime="2009-12-07T06:44:46.482Z" />
<EventRecordID>51538</EventRecordID>
<Correlation />
<Execution ProcessID="4" ThreadID="68" />
<Channel>System</Channel>
<Computer>TheMadHatter-PC</Computer>
<Security />
</System>
- <EventData>
<Data Name="DeviceObject">\Device\Http\ReqQueue</Data>
<Data Name="SecurityPackage">Kerberos</Data>
<Binary>000004000200300000000000A83A00C00000000000000000000000000000000000000000000000000E030980</Binary>
</EventData>
</Event>



Anyways I've ran out of ideas from drivers, to overheating. to power, to ram, I've tried em and found no definitive result from any , and if anyone here can assist me in any way, it would be greatly appreciated, thanks in advance