Following a power outage that outlasted our UPS’s, I noticed that two out of the three modules (MIN-6250P) in one of our server’s EMACS R3U-6460P power supply were dead. And the fan on the one module that still had an active LED was not spinning. Switching out the fans from the dead modules, I found that all the fans (SUNON KDE1204PKVX) were not functional. The working module was painfully hot when I removed it from the machine – no doubt due to the lack of heat dissipation.
So in terms of the modules dying, the following progression makes sense to me: 1) fan dies, 2) module overheats, 3) some critical component melts/fries.
However, I have a hard time believing that the power outage somehow fried the fans. More likely is that the fans were already dead or dying, and perhaps the power outage and loss of A/C were the straw that broke the camel’s back?
I am going to buy a new fan for the working module, then see if it will spin up. If it works, then that would imply that the fans are just kind of shoddy – even though they are around 5 years old. If the new fan does not spin up, then I would have to assume that somehow the power outage wreaked havoc with the modules.
UPDATE (2011-02-28): finally got around to installing a new fan in the working module; it began whirring away with no problems. So with a little splicing I’ve managed to rescue this $150 power module.