Hi, I've recently rebuilt some of my DL360's from earlier releases to SL4.3 With the HP Proliant DL360's (generation 1) single CPU units, they refuse to boot the latest 2.6.9-42.0.2.EL kernel, but boot fine from the earlier 2.6.9-34.EL kernel. There's no kernel panic from the boot screen, just hangs on boot and the machine has to be power cycled. On exactly the same model servers but with an extra CPU, booting off the latest SMP kernel boots fine. Any ideas how I can troubel-shoot this one? I've yet to disbale the "quiet" boot mode to see exactly where it hangs. I've also yet to try to boot an SMP kernel on a UP server to see if it would actually work. Thanks. Michael.