On plugging into the correct receptical

I acquired a computer from my former employer. We had an issue with it where the fan would spin up so it sounded like it would take off (and eventually shut itself down). We never figured out the issue and it was eventually sold along with other computers and equipment. I wiped the drive before we sold  it and a coworker bought it, but couldn’t get it working. I meant to help him figure it out, but somehow that never happened (sorry Derryl). He eventually gave it to me.

It sat around collecting dust until recently when I was inspired to try and get it running again. Back when it was new, it was maxed out and top of the line. Dual Xeon processors and more. I figured out the issue with it booting and installing Windows was the drive controller was set to a RAID configuration. I set it to JBOD and was able to boot.

But I still had to deal with the fan issue. I had already figured out that fan for only one of the processors was running hard and figured there was a heat issue with that processor. The other day I felt the heatsinks after the fan started taking off. The heatsink with the strange fan issue was cool and the other was warm.

I figured this meant the thermal paste wasn’t doing its job of transferring the heat from the CPU to the heatsink. I found some cheap paste I had left from an old build (it came in a multipack) and applied that (after cleaning the old paste off, of course). But the problem remained. It was late at night and I had to get up for work the next morning, so I just ordered some good quality stuff from Newegg.com and went to bed.

As I was going to sleep, I wondered if the fans were perhaps plugged in wrong. In the morning, I swapped them and checked the labels on the motherboard and saw that they were indeed plugged in to the wrong plugin. I powered it up and it ran without “taking off”. I heard one of the fans spin up every once in a while, but nothing out of the ordinary.

Now to order new memory to replace the puny 512 MB it currently has (the other 512 MB stick failed) to 8 GB. Maybe later I’ll put another 8 GB in, but first I want to figure out if the rest of the hardware is worth it.

If you were wanting an explanation on why the swapped fan cables caused the issue, read on. Basically one of the processors was running a little hot so the computer spun up its fan to cool it down. But the fan that was receiving the spin-up signal was actually on the other processor. That processor was cool enough, so it left its fan at the minimum speed. Meanwhile the fan running at the minimum speed was on the processor that was running hot and thus was not helping the situation. So the computer told that processor’s fan to spin up even more. And the cycle continued until the computer was shut down by a person or by the protection settings.

Now I have a solid computer for mostly free. The memory and the memory cooler (necessary for more than 4 GB) are going to cost a pretty penny, but it will work nicely for programming or as a server. I don’t know how well it will work for gaming, though it has PCIe which leaves me room to upgrade the graphics card.

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