Random Reboots - No BSOD

For the past two week my computer has been randomly rebooting without a BSOD. I looked under critical events in Event Viewer and found Kernel-Power Event ID 41. This happens mostly on the desktop but sometimes when playing games. I looked at this Microsoft Support Page and did everything I could under Scenario 3. I reset all overclocks to stock, ran Memtest86 for about 12 hours (no errors), my PSU has more than enough wattage. My computer is plugged into a UPS so it's not losing power from the wall. My system is water cooled so it does not get too hot under load. I redid my loop 4 months ago so there shouldn't be any problems with the thermal paste since my computer has only been restarting only in the past 2 weeks. I'm not sure how to reset the system back to system defaults. I updated my motherboards BIOS and as many drivers as I could but there are a lot of Base System Devices with yellow exclamation points that I don't know how to update.

Here is the XML View:

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
<Provider Name="Microsoft-Windows-Kernel-Power" Guid="{331C3B3A-2005-44C2-AC5E-77220C37D6B4}" />

<EventID>41</EventID>

<Version>2</Version>

<Level>1</Level>

<Task>63</Task>

<Opcode>0</Opcode>

<Keywords>0x8000000000000002</Keywords>

<TimeCreated SystemTime="2014-05-08T01:25:37.838405900Z" />

<EventRecordID>51408</EventRecordID>

<Correlation />

<Execution ProcessID="4" ThreadID="8" />

<Channel>System</Channel>

<Computer>Bob-PC</Computer>

<Security UserID="S-1-5-18" />

</System>


- <EventData>
<Data Name="BugcheckCode">0</Data>

<Data Name="BugcheckParameter1">0x0</Data>

<Data Name="BugcheckParameter2">0x0</Data>

<Data Name="BugcheckParameter3">0x0</Data>

<Data Name="BugcheckParameter4">0x0</Data>

<Data Name="SleepInProgress">false</Data>

<Data Name="PowerButtonTimestamp">0</Data>

</EventData>


</Event>