Episode 182, In Which Our Hero Does Something Amazingly Stupid

February 26th, 2006

The big plan this weekend was to reinstall Windows XP and all my applications onto a new, larger hard drive. The drive is an 80 GB Western Digital that came out of my linux file server when I migrated it to SATA disks last year. Previously, I had used an 18 GB SCSI-160 disk as both my Windows system disk and my home disk, but space was just too tight. The new 80 GB disk will give me plenty of room to grow, and the 18 GB disk will go back to being a linux system (Fedora Core 4/5) as it was before I upgraded to a dual-Xeon machine.

But you know what they say about the best-laid plans.

I have been trying to get my system to run more quietly. It’s been way too noisy for way too long now, but I’ve been too busy with other things to fool with it. Finally, Dwight over at the Chronicle wrote about his noise woes, and that got me off my duff.

The first thing I discovered is that I’d forgotten to enable my motherboard’s “Q-Fan” feature. Q-Fan lets the motherboard slow down system and CPU fans when temperatures permit. The relationship between fan speed and noise is nonlinear. By that I mean that a fan running at 3000 RPM seems to make only about 5% of the noise of a fan running at 5000 RPM. Letting the motherboard spin down the fans makes a huge difference in the noise level.

I turned on Q-Fan last week and was mostly happy with the noise reduction, but on Friday I noticed that one of the fans had a rattle in it. It was annoying, even at low fan speed. I was ready to get on with the reinstall of Windows, but I wanted to spend a few minutes first trying to cure the fan of its rattle. I poked at each of the fans as they were spinning and I quickly figured out that it was the fan on CPU number two. As I was poking it trying to figure out where I could wedge something to stop the rattle, I accidentally jammed my finger into the spinning fan blades.

My senses immediately alerted me that two things were very wrong. The first was a stabbing pain coming from my finger. The second was a hideous noise coming from the fan. Obviously one of these is much worse than the other. My finger was still attached, and only bleeding a tiny little bit, so priority one was to figure out why CPU fan number two sounded like a buzz saw chopping through carbide steel.

I immediately powered off the system – it was only running in the BIOS power monitoring page – and while I waited for the fans to spin down, I noticed a little piece of black plastic in the bottom of the case, a piece of black plastic whose appearance was as new as the pain in my finger, a piece of black plastic shaped suspiciously like a fan blade.

When the CPU fans spun to a stop, I studied the number two fan and I saw that it was, indeed, missing a blade. This explained both the hideous noise and the pain in my digit. It was a problem, but one I could deal with.

A missing fan blade is a problem of balance, and I figured I could fix the problem by removing another blade. I got out my trusty diagonal cutters, located the fan blade opposite the missing blade, and diked it out of there. I turned the computer back on. The noise was as bad as before. If anything, it was worse.

So I turned off the computer, waited for the fans to spin to a stop, and then counted the blades remaining on CPU fan number two. Three on one side. four on the other. What kind of moron designs a fan with an odd number of blades? Especially knowing that clumsy people are going to stick their fat fingers in there and break off blades?

So that’s the story of how I spent Friday night, not beginning my reinstallation of Windows, but instead driving all over Clear Lake looking for a replacement fan. I went first to Fry’s and then to EPO, but struck out in both places. That’s what I get for building my system around an oddball CPU like the socket-604 Xeon instead of something normal like a Pentium P4.

I’ve reinstalled the old, broken fan. I used some pieces of folded paper to deal with the rattle, and as long as I keep the system temperature down, the fans don’t spin fast enough to make much noise, even with number two being off balance. I’ll have to replace the it soon, though. Even though it’s not making much noise, the vibration will tear up the bearing before too long. I guess I’ll be resorting to mail order for my new fan. Maybe this time I can buy something quiet.

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