Dell Dimension Workstation A220 hangs

[ed]

I've recently noticed that my Dell Workstation 220 freezes and the only
way around is to reboot. I've looked at /var/log/messages and there is
nothing there indicating a problem. The only thing I can see is that
this is the original BIOS  (I inherited the machine from another group
at work).

I am running FC3 with the latest kernel. This problem occurred in the
previous kernel as well, but I thought it was something I was doing. I
am running about 6 FC3 machines at work and this is the only one that is
having this problem. It used to be once a week, but now it seems like a
daily occurrence.

I am also suspecting it might be a memory parity error, but can't seem
to find any logs to look at...

Would appreciate some guidance...