I have an old and faithful Dell XPS Studio desktop that I use as my main PC. I bought it when the first gen i7 came out and I use it for non development tasks. Over the years, I replaced the drives with SSDs, added Bluetooth and USB 3 and replaced the video card. To be honest, I don't see why I would retire it but one thing was driving me crazy: the loud fans. The damn thing sounded like a 747 during takeoff so I decided to take action by replacing the power supply and the CPU fan.
This is a non trivial installation as I had to remove the motherboard to replace the CPU fan mounting brackets. This thing is huge! I took measurements before ordering to make sure it would fit. It did fit...barely. The power supply installation went without issues. It nice that cables now connects to the outside of it. I think it allows the manufacturers to install larger fans inside the devices.
So far so good but when I powered the desktop, I was granted with a few beeps. A quick search led me to believe that the CMOS battery had to be replaced which I did. I also had to reset my BIOS settings but I'm still greeted with a CPU fan not working message sometimes when I boot up. A quick search on the Interwebs led me to a few articles explaining what was happening. The new fan runs at a much lower speed so it's OK. I just need to figure out a way to enter in the BIOS advanced settings, that's if it's possible on that machine (anyone knows?). Anyways, not that critical.
The desktop is now silent and it runs much much cooler. Previously, under heavy loads, the CPU temperature was in the 85C range. Now, it barely goes over 50C!!!
Can't say it was easy but it was well worth the effort and the swearing :-)