I believe this bug is duplicate with this one https://bugs.launchpad.net/ubuntu/+source/linux- source-2.6.20/+bug/83009/
Also I have the same issue with integrated NIC in Asus P5W DH motherboard. Since upgrade to the kernel 2.6.20 I am unable to boot - driver hangs all the time. -- sky2 driver hangs / softlockup https://launchpad.net/bugs/87320 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs