This past December I worked on a Dell Dimension 2400 with XP that was made, according to its Service Tag, in 2003. A local small biz runs software on it to cut vinyl letters and make signs. The PC drives a big plotter with a 4 ft. wide x 25 ft. long roll of colored vinyl that's adhered to paper, the plotter has an X-acto type of blade instead of a pen and cuts the vinyl just enough to leave it on the paper so you peel off the backing, lay the whole thing on then press onto a plastic honeycomb sign board then peel off the surround, leaving the letters stuck on. It's like a H-U-G-E "
Cricut" sort of thing only it's 4 feet wide.
Anyway, I put the software ("Flexi-Sign") on it in 2005 and about every few years it'll have an issue (malware, bad chassis fan, power supply, etc.). About 2 years ago someone kicked the USB key plugged into the back (it's $2,500 software so it has a key to authorize it) and tore it up bad. I cut up an old USB printer cable and soldered 4 wires to the key's tiny motherboard then shrunk a big sleeve of shrink tubing over the whole thing....it looks like a python had swallowed a goat but it works!
This time it had 2 issues: First, it has 1 large fan at the rear that has a green plastic shroud than helps it pull heat off the heatsink and out of the case...it was stuck. Second, it's a socket 478 for a Pentium and 2 strong spring clamps keep the heatsink clamped to the CPU and the springs hook into plastic ears on a bracket on the motherboard. Well, we all know what 20 years of heat can do to plastic so one ear broke from the constant tension, heat and age and the heatsink was doing little to cool the CPU since it lifted up and lost the thermal bond.
Anyhoo....I replaced the bracket, cleaned and re-coated both the CPU and the heatsink with thermal compound, installed a new fan and it runs great.....again. It'll probably still be runnin' when I cash in my chips.