Computer Issues

Had a very frustrating weekend with my sister-in-laws computer... fitted the new motherboard and couldn't get it to start up - messed around with the board re-setting jumpers where I thought they needed to be... no joy - took the board out of the computer again and rigged it up (in case the board was 'shorting' in the case).. no joy - reset the jumpers to where they were when the board arrived.... finally started up!
Phew, should be all plain sailing now... set the BIOS to load from the CDROM, started the system ready to load Windows.... starts to load, then just hangs doing nothing - tried this about a dozen times on Saturday - nothing doing...
Looked around in the loft for my box of PC spares (really should throw some of this stuff out) had an idea that the CD drive might be the problem (have seen this once before) - pulled one of about 6 spare CD drives out of the box - fitted it onto the motherboard - hey presto - starts to load Windows without stalling!!
I really thought that this was going to be straightforward having had quite a lot of experience with loading operating systems onto laptops when I was going through my laptop refurbishment stage (money making idea that doesn't actually make much money!). Think again... PC installations can cost you hours of time even if you are relatively experienced...
Anyway, I thought I'd share my experiences in case it helps anybody - the upshot is that now I have brought the box of PC spares out of the loft, I will work my way through them and see what bits can be discarded. I even brought down an old CRT screen, plugged it in and it worked fine for 3 minutes after which it faded into oblivion never to return, so that's going straight down the tip next week!