Screen freeze/computer lockup issue

I've been running SL on this computer for almost 2 years now, without a problem until last Monday. Since then, I have been experiencing complete screen freezes and system lockups (the little red light at the front of the box is on steadily when this happens) as soon as I go anywhere that has more than a few objects.

I've updated my graphics card drivers, I've replaced the network card. My husband, in the same room, on the same network, is not having this problem.
It only seems to happen when I'm using SL. The machine is a PC. Has anyone got any idea what I can do next? I'm flummoxed.

Unless I've had a senior moment and forgotten, I've not changed any settings - on Sunday night I was able to dance happily surrounded by 18 avatars, lights, particles etc., and then on Monday - it all ground to a halt.

Any suggestions much appreciated!

Does that happen only with SL or also other applications? The red light is probably your harddisk LED and when this is on all the time it means your computer tries to access your HD all the time. May be an indicator that it is faulty and has defect sectors and the PC can not read or write from/to it.

Thanks I asked on the Xstreet forum too, and was pointed in the direction of....dust!

Dust was indeed what it turned out to be - one big blast out later and all is well again (thought 'd let people know in case it happens to others!)

Wow...interesting . Happy all is working again for you!