I have just had to replace a DVD/RW drive.and now I cannot get the monitor to show any onscreen display.I know that the Pc is running, as it goes through its cycle as it starts. But nothing on monitor.
I have tried the monitor on my other pc to try to prove a point, that its working and it is.
Could the BIOS battery be down causing the display on Mobo from activating, the reset button doesnt seem to do anything either.
I renewed the DVD settings as was with the first and set as slave as was. Which shouldnt affect the start I would think.

have you tried removing the hardware you just placed and check whether your pc will work normally?

I'll assume you're talking about XP.

What you need to do is this:

- disconnect the drive
- disable IDE controller in device management (usually, you can disable one IDE channel, while second is enabled)
- restart with drive connected
- enable the IDE controller
- restart