Pentium 3 Fan Mod

Although the current Pentium 3 PC in the shed hasn't overheated yet, I've realised that having a shed full of people might result in more heat-related failures of computer parts - recently for example, the DuronXP 1.3 GHz CPU in PC 1 died after the last "shed LAN", and that had a gigantic copper heatsink on it, topped off with a 60mm, 4000 RPM fan. This was the first time a CPU of any kind had died on me (except for when I was trying to join the L1 bridges on another Duron with a conductive pen, for overclocking purposes, which led to me breaking it in no time).

After the DuronXP death, I decided to outfit the latest P3 PC in the shed with a fan (the previous P3 system, a HP Vectra VLi8, was broken after a BIOS flash procedure - guess whose fault that was!) After that was replaced with an almost-identical HP P3 motherboard, which became a new spare internet PC in the house, I decided to get another P3 microATX board, and put it a compact mini tower case I had kicking about. This then ended up in the shed after the dual Pentium 3 "server" PC gave me yet another pain in the backside, forcing me to relegate it to the position of armrest / footrest combo.

Anyway, the new P3 PC case is very limited on cooling options - only one 80mm fan bay is available, at the front of the case. So, I decided to find a way to attach a fan directly onto the CPU, a 550MHz P3 with a big heatsink; after experimenting with hooking bolts between the heatsink fins (too loose), I settled for rubber bands. To do this yourself, you'll need one fan, 40-60mm in size, with four boltholes in each corner, and four rubber bands. Don't use the ones postmen drop on the pavement, they're too thick & inflexible for this mod. (Optional: to eliminate fan vibration noise, put some silicone rubber grommets or pieces of foam rubber between where the fan and heatsink make contact.)

Step 1:

Push one rubber band through each bolthole to form two small loops on the top & bottom of each one, like this:
Also optional: balancing your processor on 1 penny and 2 penny pieces

Step 2:

Push your index finger through the first two rubber-band loops which go through the right bolthole closest to the processor PCB, and pull them under the flat bit at the base of the heatsink (afterwards, repeat this for the left bolthole):
Pulling the rubber bands under the heatsink base

Step 3:

Push your index finger through the next two rubber-band loops on the right bolthole at the end of the heatsink's fins (or reaching past the fins, if you have a fan over 40mm), and hook them underneath the right-hand heatsink retention clip (afterwards, repeat this for the left one):
Pulling the rubber bands under the heatsink retention clips

Step 4:

Check the rubber bands to make sure they're all securely in place:
Wow, none of the rubber bands have snapped off yet!

Step 5:

Put your P3 back in the PC, plug the fan in, and with any luck it should work. Job done!
Plugged back in and ready to go! (Eventually)

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