My CRDOM does not allow my PC Start

I Have a PC with a PCChips M598LMR Mainboard, SIS 530 Chipset, 64MB RAM, a AMD K62+ 500Mhz and a hard disk with 10 GB.
So…my pc has had a strange behaivor. Every time I put a CDROM disk into the drive it just restarting and can?t start normally again.
Then, i eject the cdrom disk. Done that the PC start with no problem.
To engage the focus of the problem…I install the cdrom drive ( w/ cdrom disk within) in another pc…
So, to my surprise the other pc starts normally with no problem.
So, Can you tell me what could be happening?
Thanks,
Pertheus