FreeBSD unstable on Dell 1750 using SMP?

[Rutger Bevaart]

hello list,

For the past year we've been running several Dell PowerEdge 1750 servers
on FreeBSD 4.10, 4.11 and 5.3. All these machines have dual Xeons running
with HT enabled. This install has proven to be unstable in that the
machine will reboot between 3 days and 170 days without apparant reason.
No log is written. Other machines we have with a single CPU (HT enabled)
do not experience this problem.

As it is present in both 4.x and 5.x and googling the last year has not
revealed similar experience I'm consulting this list. As all of these
machines are productions machines that have a continuous load (not heavly
load, but a light average - some peaks) it's not easy to experiment with
HT setting etc. I dislike driving to the datacenter for locked systems
with fubarred kernels ;-)

The only error i've ever seen just before a reboot is "bge0: discard frame
w/o packet header" on the 5.3 machine.

Any clues or help greatly appreciated!

Regards
Rutger Bevaart