5.4-STABLE hangs every few days

[Brad Waite]

I'm running 5.4-STABLE on a dual Xeon Tyan i7500 which is freezing up 
every few days.  I'm still fighting with my box to find out where my 
problem is.  I would appreciate any pointers to diagnose and/or fix 
this.  I can't find anything on the lists or in the handbook on this 
level of troubleshooting.

I've got INVARIANTS support turned on, but I can't tell any difference 
between that and the non-INVARIANTS kernel.  When I break into the 
debugger there's no locks or lockedvnods and I can't see anything that 
*looks* wrong in the threads or processes.

Rebooting every few days is worse than an NT server!

How do I determine if it's a hardware issue, namely RAM or CPU?  Can 
breaking into the debugger tell me that, or do I have to start swapping 
pieces out?

Any help appreciated.