I've been arguing with Mission Control's PC the last couple of weekends. It's a monster server-class PC that we bought used from someone who picked up a bunch of them during the liquidation of the renderfarm for Star Wars: The Clone Wars; it was allegedly used to do some of the rendering for the movie.
Lately, it's been shutting itself off after a while. Poking around, we discovered that the little fan on one of the motherboard chips wasn't starting up; if we gave it a nudge when we turned the machine it, it'd start going and everything was fine.
Until recently.
So, it was time to buy a new fan. I contacted the manufacturer and they told me I needed to look at a 3rd party solution, but didn't offer any pointers. Problem is that the fan in question is right next to the slot used for the video card and sits in the space underneath the part of the card that hangs over motherboard. So the average fan won't work, because it's too tall to fit in that space.
Finally wound up buying this one, and it just barely fits. It's a couple of millimeters taller than the original fan, so it's a close thing, but fit it does.
So I finally got brave enough to take the motherboard out of the box (you can't take the bottom of the box, so I had to pull the motherboard to clip the plastic pin thingies holding the fan in so I could pry it off) and change the fan.
I powered the thing up and the fan spun and the machine booted, so I was happy.
For about 15 seconds or so, after which the machine shut itself off.
When I turned it back on, instead of booting all I got was a constant loud beep.
There's a power indication LED on the motherboard; when you have the thing plugged in, the LED is green. The manual says "LED on = power to board. LED off = no power to board."
Trouble is, when I plugged and got the loud beep the LED was red. It was on, but it wasn't green. The manual says nothing about the expected color of the LED, nor does it even mention that it's a multi-color LED.
By now, of course, I'm convinced that I've somehow killed the machine. I don't have an anti-static workplace at home to do this sort of thing and I have zapped things in the past (that's how I wound up with a framed CVAX chip hanging on my wall), so I'm convinced that's what I've done.
But this sort of thing smells like a bad power supply, so I decide to check that out anyway. Unplug the supply, short the pins that get connected when you push the power button, and put a voltmeter on the +12v: +8v. Similarly, the +5v is only giving me +3v.
So clearly, the power supply has died and, just because God is some sort of joker, decided to do it just after I had worked on the system.
Unless, of course, I had somehow managed to kill the power supply.
Regardless, it was time for a new power supply.
Minor complication: looking around the web, I see that this particular motherboard is kind of finicky; lots of folks having problems coming up with a supply that will work for it, and the general consensus of opinion is that you should stick to the exact supply recommended by SuperMicro.
The only easy way I found to get one involved buying a whole new case with the power supply included, which is what I did, the plan being to move the new power supply into the old case, so that I don't have to move all the drives and everything to the new case.
When I took the new supply out of the new case, I discovered that one of the screws was in a position that would probably require me to take the motherboard out just to get at it. Nevertheless, I pulled the supply and grumbled about folks that design cases.
Looking at the old supply, though, I discovered that I could slip a wrench alongside
the supply and get to that screw without pulling the motherboard. Of course, it would be completely impossible for me to put the screw back in, but I don't mind; there are four other screws holding the power supply in. So that's what I did.
Fired the thing up. It booted.
I'm always amazed when something I've fiddled with works when I'm done with it. That doesn't always happen.
Anyway, I now have a spare case. It's a hefty, good quality case, too; the sort of case Ken Olsen could sit on without collapsing it.
But the new case doesn't have the one feature of the old case that I really liked: the old case has four hot-swap drive bays; each bay has a nice drawer holding the drive with a cute little handle you can pop open to pull the drive from the system. The new case just has your average, everyday drive bay.
Maybe I should mention that the motherboard is a SuperMicro H8DCE just in case someone is googling for a fan that fits it or an explanation of what a red D25 means.
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