Hello, Having not been able to run a kernel without locking up since 2.6.9-34.0.2.EL, I think I have found the 'fix'. There are numerous post about this and all suggest its related to ACPI. For me, its APIC. I added the following to grub.conf: noapic apic=off. Been up now 4 days, 22 mins. running 2.6.9-78.0.8.EL. Previously I could get maybe 4 - 6 hours before locking up. Another thing I noticed is that eth1 was on interrupt 9, the same as ACPI. I also changed the interrupt for ACPI in CMOS to 10. I'm happy as a pig in slop!!! I may now upgrade to 5.2.