It was indeed the power supply. It's happy again now.

-Steve

G J wrote:
> Does the sound sound like a fan? I'm not familiar with servers all that 
> much but the older Dell I do have has a power regulation module, and I 
> believe these are just switch mode power supplies acting as DC to DC 
> converters, the high frequency transformers in switch mode power 
> supplies can make a noise similar to a fan...just a shot in the dark, 
> but if there are no other moving parts, a buzzing transformer is pretty 
> much all that's left to make a noise. My 2 cents.
> 
> =Jesse=
>