Hi,
I have an alphastation 255 (233Mhz) on which I get machine check during
heavy usage: pci bridge fault while heavy usage (copy from a NFS server
to a local IDE disk) or processor fault during heavy CPU usage (package
compile). I tried 2 different RAM sets, and tested the 2 RAM bank on
motherboard individually. So this doesn't seem to be a problem with RAM
or with the RAM socket on motherboard (or several of them are brocken).
Opening the case just after such a crash, I noticed that the CPU and chips
around it are quite hot (I can barely keep a finger on them). The front fan
looks OK, but maybe the air flow is lower than it was. Any comment on this ?

Also, I changed a bit of hardware: added a 3com 100Mbs NIC (also tried
a 21140-based NIC, didn't help), a pciide adapter (tried different Ultra33 and
Ultra66 models) with and IDE disk (I keept the origial SCSI disk for system)
and remplaced the floppy drive with a SCSI ZIP. I keept the origial SCSI
cdrom drive. The 255 manual says it can support up to 3 internal SCSI disk in
addition to the CD, so I guess the power supply is enouth for all this
(I don't think the ZIP eats significantly more than a floppy drive when idle,
and I can't see the extra nic + extra IDE controller eating more than
a hard disk). Again, any comments on this ?

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 24 ans d'experience feront toujours la difference
--