XP Not booting from HD

Have a problem here, while installing XP on a PIV system with a Intel MB, setup copies files to HD, but does not boot from the HD again on restarting.
BIOS options are all ok – in order with HD, CD-ROM etc.
The HD is master, and CD-Rom is Primary Slave.
It keeps booting from CD ROM everytime.

How do I get across this problem ??
PS: Tried installing Ubuntu but got the same problem. Also, the HD is properly formatted – FAT32 and in ext3.

Thanks
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