Computer keeps crashing cant find HDD drives at boot up

Okay so i have a dell xps 600 running Windows 7 32-bit,2 gigs of ram,2Nvidia 7800 gtx cards(SLI), and 2 250 gig HDD running in RAID 0. Now the issues

Sometime around early last month i noticed my computer would be off when i had left it on hours before just recently i was on my computer when it physically shut itself off out of nowhere, when it reboots itself it says cant find drive 0 and 1 and at the bottom of the screen it says no disk reserved for raid use. its my HDD's can anyone confirm. i have tried different sata cables and i have tried changing my memory as well as the sli bridge.

I looked at the event viewer and i found where it shuts down it says this:

<Provider Name="Microsoft-Windows-Kernel-Power" Guid="{331C3B3A-2005-44C2-AC5E-77220C37D6B4}" />
<TimeCreated SystemTime="2010-08-22T02:35:52.562500000Z" />
<Correlation />
<Execution ProcessID="4" ThreadID="8" />
<Security UserID="S-1-5-18" />
- <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>