RAID Error after Formatting Hard Drive

Ok, so I just bought 3 Western Digital Caviar SE16 WD2500KS 250GB hard drives, to go with the one I already had in my computer. I stuck them all in the computer, set up the RAID driver floppy disk, set up the RAID to use RAID 0+1, (striping and mirroring), and then started installing Windows Xp Home.

I partitioned the RAIDed hard drives into 4 partitions. A 50GB, a 200GB, a 100GB, and a 115GB. Now, everything went smoothly, I got Windows up and running, and everything was just peachy. Now, as some of you know, you need to format the partitions after you install Windows. So, I formated the 200GB, and the 100GB (the 50 was already done by the installation). I would reboot after each format, to make sure everything was ok, and that the RAID array was fine.

Now, after I formated the 115GB partition, I rebooted, and found that there was an error. It used to show an Array at index 0, and the status was "Healthy" etc. Now, it shows two arrays, the one at index 0 is "Degraded" and the array at index 1 says "Error". I tryed to rebuild the array, and nothing happened.

I don't think it is the hard drive failing, because I was able to wipe the drives, and do it all over again. Everything went fine, and now after formatting that last partition, it has an error. I should also mention that both times the error has been with the same hard drive.

Does anyone know what could be the problem? It's very frustrating to have to wait 4 hours to install and format everything, and then just when you're about to be done, it gives you an error. I would really appreciate any help I can get, cause I have no idea what to do.

System Specs:

Motherboard – Asus M2N-SLI Deluxe AM2

CPU – AMD Athlon 64 X2 4200+ AM2 2.2Ghz

RAM – Corsair XMS2 DDR2 800 2x1Gb 5.5.5.18

Video Card – eVGA 7900GT KO PCI-Express 256MB

Hard Drives – 4x WD Cavier SE16 SATA 250GB.

Power Supply – FSP Epsilon FX600-GLN 600W 4x [email protected]= 60A total