I've been troubleshooting this computer for some time now. At first, I disabled RAID because of the blue screens and I found that one was bad and the second of the RAID 1 appeared fine. Well, I installed XP to ensure it would work and that was extremely slow. My client didn't have a disc to XP MCE, but instead bought Windows 7. The installation took about 12 hours and the system is often unresponsive. On resource monitor, the 2.13Ghz Conroe CPU is barely tapped and the 2GB of RAM is barely at 30%. However, the system takes forever to boot and it very often stops responding for a period of time.
I did my research and found out that this model--original specs--can handle 7 better than this. I told the client it was probably an HDD error, as it seems to hang everytime the system must access the HDD. I can't even run the Index to find out what the systems rating is.
I memtested the RAM and chkdsk the HDDs before removing the first because of its clear faults in its inability to hold an OS installation. I recently installed the 2.5.3 BIOS update, but I haven't had a chance to install a newer version of Intel Matrix Manager.