I recieved a set of APIC errors in my logs a couple days ago. This is the only time they've ever appeared before or since. My understanding is that anything from 0-3 is a hardware error, but everything I've found in my research shows people having problems with the error showing up endlessly - over and over and over and over. I'm concerned that this may indicate pending major problems?

Also, I know that this error, essentially, means that the controller failed a checksum.

kernel: APIC error on CPU1: 02(02)
kernel: APIC error on CPU0: 02(02)

It's a Tyan Tiger 4226 mobo with dual 1500mghz AMD's. It has been running on this same machine for three full years. No hardware has been changed in that time. Currently, the machine has not been restarted for any reason in more than two months. So I'm not sure why this error would occur out of nowhere - and just one time.

Any help would be appreciated.

it could be that your apic buss just got overwhelmed there for a second and corrupted two messages sent to the cpus

it's nasty and needs some attention if it keeps up but heh -- you said it only happened that once ;~)