Hi, I have been trying to run 2.4.24 on a quad opteron (Quartet motherboard, from Celestica). If I enable NUMA, the kernel panics during bootup most of the times. Occasionally it will boot ok (without me doing anything special). I have tried the various noapic, idle=poll without success. I can get it to consistently boot if I specify pci=off, but then the machine it is not of great use, since the RAID card is mounted on a PCI slot... When it crashes, I get (I am copying from the screen by hand...) CPU 3 PID:1, comm, swapper not tainted RIP: 0010:[<ffffffff801421e7>] RSP:0000:0000010003c33e78 EFLAGFS 00010016 The CPU number varies (but never 0), the content of RIP is always the same. I can copy more, if necessary. The BIOS is the most recent (upgraded to fix sluggish memory). Note that kernel 2.4.19-NUMA boots fine as so does 2.6.4, with NUMA enabled. THe reason I am trying to use 2.4.24 is that when it works is gives good performance and has openAFS supported. I tried to get openAFS to work on 2.4.19-NUMA, without luck. OpeanAFS has not been ported yet to 2.6... Any help will ber greatly appreciated. Thank you Alberto Scotti -- Alberto Scotti Asst. Prof. Dept. of Marine Sciences CB 3300 University of North Carolina Chapel Hill, NC 27599-3300 919-962-9454 (w) 919-962-1254 (f)