- wrong CD (not bootable) --> check on another PC
- BIOS not set to boot from CD (although you say so)
- CD drive defective --> check with another (proven) bootable CD, e.g. a Linux live Cd
I have an HP tx1000 notebook and want to remove vista and install XP. I've erased the hard drive, but when I put in the XP disk it doesn't boot. It just says no operating system found. I have it set up to boot from the CD first.