The most expensive cost of GPU mining is purchasing equipment and one of the most overlooked pieces are the case fans. People tend to just run them and grind them into the ground because of their relatively low cost; however, if you run 8 to 12 case fans per rig and have multiple rigs the cost
of replacing fans every few years does eat into profits. Knowing how to properly clean and oil case fans is an essential skill for every crypto-miner to learn. The same skill applies to GPU, CPU and power supply fans, but off course they require a partial disassembly in most cases.

Here we cover the basics of cleaning and oil a case fan. You will need a can of compressed air and as always take proper steps to prevent electrostatic discharge.

I use an open air rig frame with my case lined up in rows of four, each held onto the frame by four screws. After turning off the rig and unplugging the power supplies, I ground myself to the outside case of a power supply to prevent ESD (electrostatic discharge). While the fans are still mounted,
I hold the blades still with one hand while using compressed air to blow off dust from both sides of each blade. Depending on how long it has been since the last cleaning, I follow up and clean the blades gently with a small foam paint brush then gently blow off the blades again with compressed air. I repeat these steps for all the case fans before I move on to oiling the bearings.

All fans on a computer have lubrication around their bearings that runs dry due to heat caused by friction and accumulation of dust speeds up the process. If you hear noise coming from the fans that you never used to hear i is a sign that the bearings are starting to wear out. Fans with bad bearings begin to slow and are less effective and removing heat. Again with case fans, I get it, they are cheap; however, when that fan is on your power supply, cpu, or gpus you are talking big bucks for ignoring a regular maintenance schedule.

The oil you should be using is a three-in-one oil that has a mineral oil base or sewing machine oil. I personally like ones that have the small oiler tip built in. These are cheap and easily found all over Amazon and other retails. When in doubt just buy the sewing machine oils.

I personally unscrew my case fans from the frame so I can set them in a horizontal position so I don't have to fight gravity when I oil the bearings. Almost all fans have a sticker on the front plate. After removing the sticker you can see directly the shaft and bearings or you will see a plastic plug covering them that you must first pop-out. If at all possible just peel the sticker back and oil the bearings. Fill the bearing with a few drops of oil, but don't overflow it. Turn the blades a few times in each direction to get the oil spread around the bearings. Replace the plug (if applicable) and the sticker. If you tore the sticker or it lost adhesion, covering it with a piece of tap. I like the thin aluminum tapes and just cut it out in a circular pattern to
match the original.

The same procedure applies to video card and power supply fans. On the power supplies you have to contend with removing a few screws to take off the finger guard. I personally like to clean and oil all the fans twice a year.