grub hangs

[el Muerté]

i just installed Fedora Core 4 on my external USB HDD. I installed GRUB to the USB drive since the install program wouldn't recognize my SATA RAID array (my main drives) and set my BIOS to boot from USB. Right after the POST my computer starts loading GRUB but hangs, all it displays is "GRUB" and locks right up. Any ideas how I could fix this?

[hard candy]

1. In Grub's menu.lst, the usb drives needs to be hd0 and the drive inside of the computer should be hd1.
2. In the computer bios, keep the cd/dvd as the first boot device, the usb drive as the second, and then the internal hard drives.

[saikee]

As far as I am aware Grub doesn't boot from a USB device. It hangs because the USB response time is too slow.