Why would a Windows 2000 box freeze and lock up completely?

It's only started happening recently (in the last few months)

It started happening when it was 1st switched on in the morning and would happen for 1 or 2 reboots, then it would be fine for the rest of the day.

Now it's started happening completely at random, and seems to be getting worse.

I've opened it up and ensured everything is seated correctly and removed all the dust. All the fans are working.

Could it be a software issue which is fixable by an over-install, or am I likely to be looking at a bill for replacement components?

Why would a Windows 2000 box freeze and lock up completely?windows themes

Point to the problems we have had recently with windows 2000 it seems that after a while it can become unstable.

Why would a Windows 2000 box freeze and lock up completely?internet explorer 7 internet explorer

How is the hard drive ? Could be on the way out, and need replacing.

Has the workload increased ?

Windows is absolute rubbish, isn't it ?
It could be possible hardware failure. My guess would be that the processor is overheating.

Have you ever taken the case off the side of your computer and blown the fans out with Compressed air? The fans are there to keep the interior of your PC cool. If they are clogged with dust and dirt then they cannot move the air effeciently, thus resulting in an overheated PC that reboots itslef, locks up and shuts down ocassionally.
deffinetly sound like hardware problems more likley PSU need a replace but over install never hurt anything.
Ive seen similar problems when bad RAM is present. Check with RAM you know its working. If you do get the machine up, try running a diagnostic tool on the whole computer to try and figure out the problem. Windows 2k is by far more stable than XP so these kind of problems usually are because of faulty hardware. You can also check the processor temperature and fan speed on the BIOS.