Problems with SMP on Alpha UP2000+

Hi,

I have a UP2000+ system with dual 21264 @ 667MHz/4MB cache and 2GB RAM. The
system runs fine with RedHat 7.2 Linux (downloaded from hp website) with an
2.4 SMP kernel. However, running Gentoo with an SMP kernel will eventually
make the system freeze (i.e make -j2 when building a new kernel only lasts
for a 30 seconds or so). I've also tried NetBSD-5.1, FreeBSD-6.4, and a few
other Linux distros with the 2.6 kernel (make -j2 makes the system freeze).
It seems like Linux kernel 2.4 is the only OS that works with SMP on my
system. Has anyone else experienced something similar with an UP2000+ Alpha
system? First I suspected faulty hardware, but RedHat 7.2 seems to work just
fine so...

I heard somewhere that Linux going from 2.4 to 2.6 made some significant
re-structuring of the SMP code that broke SMP support on some systems?

The system has a Matrox Millenium and a 3Com 3c509B Ethernet card and a SCSI
disk hooked up to the on-board SCSI. I've tried unplugging the NIC and a
using a DEC PowerStorm 3D30 in stead of the Matrox Millenium, different CPU
modules and different RAM modules. All with the same results. There are no
error messages to be seen anywhere when the system freezes up.


Regards

Magnus