Hardware problem

Good afternoon folks, i'm posting this from a fresh install of Ubuntu 5.10, because the machine is rather decked it seems.

The story so far, came home yesterday to find PC in a BSOD state, I rebooted and got an error saying something along the lines of 'cannot load windows - press Ctrl + Alt + Delete to reboot' (sorry for how vague description - i've been workin on this machine non stop since then basically and seen a hell of a lot of errors.

Ok I thought, I've nothing valuable installed - i'll just reformat and be done with it, which I did - and it worked, until I rebooted to install something - and got the same error!

I had PowerMax on a floppy, so I ran it overnight and checked in the morning and it said "this HD is failing" - so I put in a spare 5400 RPM drive I had to get a temporary install on it, but it was suddenly failing aswell, odd, given that I took it out of its previous machine in perfect health and its been in an antistatic bag ever since.

I managed to install linux now, on the first HD I mentioned, which is odd - because I couldn't earlier.

Does this seem like a HD problem, IDE cable problem (only thing I haven't got here to swap out, although I swapped the one from CD -> Mobo onto HD -> Mobo and got the same error), or potentially a Motherboard problem?

Any help mucho appreciated!

Cheers,
David

Update: I remembered during my failed Ubuntu installation attempts a reference to an error creating a RAMdisk, so I ran Memtest and it threw up errors around the 800MiB mark, I removed my 3rd stick of RAM (I run 512MiB,256MiB,256MiB) and Ubuntu installed - i've just formatted the drive and installed Windows sucessfully - can this be put down to faulty RAM, given all that has happened?

I think so, BSOD is most of the time RAM related. But Im not saying it for sure though :D

Yep, its this 2nd stick of GEIL RAM I got given by a mate from Uni, first one works fine - I just tried the second one in my 3rd slot again and got the same 'Ctrl + Alt + Delete' error - put in a 256MiB stick I had and it worked fine - so now i've got 1GiB of working RAM :)

Edit: having said that, i got the error when I had 1280MiB of RAM installed, could it be the odd volume of RAM thats making it go funny - 512+256+512?

I'll try with 512 + 512 tomorrow and report back :)