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How to build a stereo - Part TwoPosted by Andrew Poelstra on May 8, 2006.

DISCLAIMER: I am not responsible for any personal injury you aquire when copying what I did here. I strongly recommend that you don't try this, and bear in mind that the fact that I do stuff like this is not a reason for you to. Kids, I do stuff like this, and I'm always getting hit by cars and electrocuted and impaled on something or other. Trust me, you don't want to live like that. Now, part two deals entirely with putting a new fan in my power supply. This would normally be a minor issue consisting of the following:

Unplugging the power supply and leaving it overnight to drain (there are huge dangerous capacitors in there).
Opening the power supply and noting how the fan is plugged in.
Removing the fan and disposing of it however you want.
Installing the new fan as the old one was.
Putting the cover back on the power supply, screwing it together, and you're done!

Unfortunately, my power supply was shockingly old (about 10 or 12 years) and my fan was shockingly new (about 10 to 12 days). So, they weren't 100% compatible. I checked to make sure they used the same voltage, which they did (12 volts), and other than that, theoretical compatibility was assumed to be okay. Physical compatibility, however, was not. For the remainder of this tutorial I had a friend over named Nick. All he did was sit and laugh at me, but he was necessary because if I died, someone needed to call an ambulance. The first issue we encountered was that the power supply had funny screws. These were like a torx, but had a nib in the middle, meaning that a regular torx wouldn't work properly. After an hour or so of deliberation, I hit upon a plan. We took the power supply outside, and I put the screwdriver into the screw and hit it with a hammer. HAMMER SAFETY WARNING: Don't hit yourself. I almost broke my hand, and that was one of the reasons Nick was laughing at me. This seemed like a bad idea, but it served to flatten the nib and weaken the screw in place, with only minor denting of the surrounding area. After that, we removed the screws and left them for another day; we had some decent '+' screws laying around that fit. After getting into the power supply, we were glad we were outside. We went in and got a large fan, and blew the eight kilograms of dust away from us. My neighbor wasn't happy about the grey cloud, especially as he's a firefighter and all, but we had opened a power supply! From there we removed the old fan, and noted some interesting characteristics:

If you stuck your finger in it and tried to move the blade, it wouldn't spin.
When you plugged it in, it warmed up.
Therefore, if we had left that fan in there, the power supply would have caught fire and exploded.

Now that we knew that we were doing the right thing, we pressed on, and opened the new fan. It is one of those cool ones with the blue LEDs. As I learned later, blue LEDs aren't cool in the middle of the night when you're trying to sleep and you have a blue light that you can read by lighting up the darkness. Part 3 fixed that, but we aren't there yet. However, due to the age of the power supply, we encountered some problems. The original fan used a two-prong setup, with positive on the right and negative on the left, like so:

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 N P

The new fan used a three prong setup, with an extra pin for speed data
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 D N P

This would have been fine, but the 3-prong had a tab preventing me from putting it into a two-prong port. It's almost as if I'm not supposed to be doing this. Stupid hardware manufacturers. It took me 4 hours to figure out this solution, but in the end it was relatively simple. I took another 3-prong socket and switched some wires, taping it onto the original socket. Now I had, coming off of the new fan, this:

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 D P N
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 D N P

Seems simple, but taping that together and plugging it in (there wasn't room for my hand, so I had to use needlenose pliers), was a pain. In the end, though, it was worth it. When I get around to it I'll post a picture of my power supply, which is currently being used in a computer. If that doesn't scare you, consider this: the power supply that I beat open with a hammer is currently hosting this blog. Update: Boom! The blog recently moved to a newer, less explody server.