I am attempting a dual-boot setup with windows XP and Mandriva 2008. I have two hard drives and a motherboard that supports both primary and secondary masters. I have XP installed on the secondary master and have installed Mandriva on the primary master. I have selected GRUB as the loader. The problem is that once the system goes through the POST and recognizes the drives, it reboots; this cycle continues until it is manually interrupted. I never see the GRUB menu, so I'm not sure it's even getting to that. Where/how should I start troubleshooting?

Altho you have 2 ide controllers there are some easy tests you can do to check what is happening.

1) I suspect grub the bootloader was not installed into the mbr of the drive that the bios is trying to load

2) b4 confirming one...assuming you know about static electricity and grounding your hand before touching a turned off computer...
swap the ide cables ....the wide ribbons....assuming both are jumpered as masters and then see if you get XP's ntldr bootloader or grub or nothing

3) if you have a live cd it is very easy to re-install or install grub into the mbr for the first drive.

4) I assume you know that most mobos have first drive on outer edge and second drive is inwards?

5) I assume you know how to set the jumpers for IDE drives to master? It may be that the first drive has 2 slaves on it or just one slave?

6) Its unusual for a MS person to swap the drives around unless that were trying to protect the xp bootloader, so if you have time, tell us what steps you took in swapping and then installing linux.

7) if you think it is the bootloader in first drive error....and you have no live cd....Mdv has an option to re-install bootloader or you can use the console in rescue mode with commands

grub
root (hd0)
setup (hd0,0)
quit

but those numbers may be wrong so check my trouble shooter on how to confirm if you want.

hd0,0 assumes you put all of linux into the first partition on the first detected drive

Thanks for taking the time for such a detailed response. The first thing I need to try is in your second bullet - "...assuming both are jumpered as masters." I thought I remembered taking that step; however, in looking through the manual last night, I noticed that this drive requires two jumpers for a master configuration, and I have only 1. I'll try to pick up a second jumper today and keep you advised how that works. Thanks again for the response.