[Hampshire] [OT] Hardware Diagnosis

Evening all

I'm experiencing a couple of problems with what has up to now been my most
stable of PCs. It does run XP but (as some of you will know) that's
because I run some special software for the visually impaired which doesn't
exist for Linux... yet.

Anyways back to the plot, it's developed a strange error on boot. It
either:
1) Says I have a disk read error and please Ctrl+Alt+Del. If I do this 3-4
times, hey presto - it boots up ok - no safe mode or anything.
2) Says I have a missing registry component. This is usually curtains on
an XP box but again, a few soft reboots has (thus far) fixed it. Quite why
this should be is beyond me.

What I need really is a double check of my diagnosis (and yes - a backup is
in progress).

I'm thinking 1) above is caused by a flat CMOS battery. I've seen this
exact same behaviour on a PC a while back - however in that case, the PC was
ancient - some 8 years old - this is only 3 years old. Interestingly I
went into the BIOS and it can still see all the drives - so I may be wrong
about a flat battery.

If not a flat battery, then it points to a faulty primary hard disk. The
one in question is 40Gb PATA and has been in use for 3 years also. The odd
thing is if it's an error on the disk, it's seemingly broken one moment,
then fixed after a reboot - most odd.

Do these conclusions seem sound or have I missed something obvious?

Cheers
Rob