Hard drive missing (RAID0)

Hi THW

Recently my computer has been undergoing a few BSODs. The error associated is a kernel inpage data error. After rebooting, it will work (after a hefty boot time) albeit with one of my two TB HDDs missing. The BIOS doesn't see it, windows doesn't see it. A strange combination of cooling it down, changing the sata port and rebooting tends to get it going again until the next BSOD.

Normally I would accept it as a drive failure and resign myself to losing 1.5TB~ of data and reinstalling windows. However, this problem seems to be multi-faceted, as a similar BSOD was "fixed" days before by removing one of my 2GB ram sticks. The machine would not boot at all with that particular piece of RAM, so it's gone. Now it won't see this HDD, although I am pretty sure it's operational. Disk manager calls disk1 missing, all partitions used by it as failed, and gives no reaction to reactivation.

I really don't want to lose all of this data. I don't have any discs or USB drives to boot from at this point either.

So should I be looking to replace a motherboard, a PSU, or what?

Information:

Two 7200 SATA HDDs in RAID0. Drives C: E: S: T:

C: is 30GB windows on disk0, E: is 500GB of data across both disks, S: is 10GB of temp/pagefile (across the innermost disk sectors of both disks), T: is 1.3TB more data spread evenly across both disks. I think this is a software RAID with both disks being dynamic.

AMD Phenom II black edition 3100Mhz stock
ATI Radeon HD 4770 Sapphire
W7 ultimate x64
4(2)GB Crucial DDR2 RAM
Some ASUS mobo AM2+
a 350W PSU (I know it's low but I have had 2 fail on me already)