i've recently arrived at university, and i am studying computer science. It was advised to use linux on your home pc's for compatibility with the lab pc's. I first installed fedora to dual boot with XP Pro on my system, i re-installed it once to install more options. Both of these attempts went ok, and i could easily dual boot between the two systems. It was then advised by my department to install CentOS-4, again for compatibility. The installation progress seemed to be going fine and was very similiar to Fedora. I have previously partioned 8 gb of hard drive space, for linux and 1gb for a swap partition. The installation went fine and i was looking foward to using it when the problems begun. Ever since then, after my computer rebooted, i have not been able to get past the bootup and bios screens, the computer just restarts itself. I set XP Pro as my default os, but i also did this on Fedora and it worked fine. With my limited knowledge i could only guess that the problem was down to the bootloader, so i tried to re-install CentOS, however i now can't get to the installtion screen. I can get to the text bit, which alows you to install in a GUI or CLI, but after pressing enter i get a 'ide-cd: cmd 0x25 timed out' , 'hdc lost interupt' , 'irq11 : nobody cared!', i get these errors followed by error codes like '[<c0103c4a>]_report_bad_irq_+0x1c/0x70', i get this 3 times then the installation continues to the blue screen bit. The first drivers loads fine, but then the 'Loading SCSI Drive : loading ata_piix driver' hangs indefintely.

My system is:
ASUS P4P800-Deluxe
1 GB - RAM (Twinmos 512 x 2 )
Intel P4 2.8ghz (H/T)
Maxtor 80gb SATA HDD
Radeon 9800xt

My hard drive and dvd drive are both 2 weeks old, the rest of the system is about 2 years old. I have used the dvd drive since i got it, for the burning and installation of Fedora and CentOS, amongst other things, and have had absolutly no problems with it.

Sorry if explanations a bit long winded, i'm still quite a newbie at linux, but want to give it ago, any help would be much appreciated.