Turn your computer off and take the power cable out of the
PSU.
Disconnect everything that is connected to the CD-ROM drive including the power cable..
Make sure the cable is connected to the motherboard properly (remove it and put it back on if need be)
**Check the pins on the back on the CD-ROM and make sure none of them have been bent.**
Then connect the IDE cable back onto the CD-ROM with the power and plug you power cable back into the
PSU.
Turn your machine on and see whether it works.