disk spinning continuously + cpu possibly overheating = sudden death

[Chuck Swiger]

On Jul 9, 2011, at 3:53 AM, Manish Jain wrote:
> I am running FreeBSD-8.2-amd64 on a Western Digital 320 GD disk and a
>   quad-core AMD Phenom processor. After booting, the disk keeps
>   continuously (meaning continuous I/O) and after a couple of hours (on
>   the console with the X server not running), suddenly the whole system
>   dies, powering off in a flash. I suspect the continuous I/O is causing
>   is a CPU overheat which results in this behaviour.

While you probably do have flaky hardware causing problems, even under the worst case situation, a modern hard drive doesn't use more than about 10W even under full load (ie, continuous writes).  Compare that with the 125W thermal design rating of a 4-core Phenom.  If your system is overheating, it's not because of what a hard drive is doing.

It should be easy to tell if thermals are an issue-- is the CPU heat sink getting too hot to touch just before this shutdown?  If so, it's likely to be a problem with a cooling fan or heatsink attachment.

Also, what is it that makes you think your disk is doing continuous I/O?
What does "iostat 5" or similar show?

Regards,
-- 
-Chuck