Owing to some problems (explained in another thread), I decided to take my PC down to its bare minimum of useful components and then put it back together piece by piece to see if I could locate the device causing my problems.
In the course of this, I've disconnected my hard drives. Having put everything back, when the PC tries to boot from the hard drive, it can't seem to "see" them.
The hard drives are master and slave on the primary IDE channel. On the secondary I have a DVD ROM and a DVD RW, which the PC sees fine. When I go into the BIOS, it seems to recognise that a drive is connected but doesn't make it available as an option to boot from. It does not show up on the BIOS startup screen at all, just the two DVD drives.
I can't help but think that I've done something very basic wrong. Any ideas? Any ideas what I should look for?