This is why you need to open up your PC occasionally and give it a bit of TLC. The pile of grubby dust above is just six months worth from our always on media server.
I got into the habit of cleaning it out regularly after it started (unsurprisingly) to become pretty noisy and given that it is in our lounge that became an issue. It is amazing the difference that a really good clean makes.
One important thing is that you MUST NOT use your normal hoover to suck out the dirt. This is a bad idea as it certainly take up the dust but most of the delicate components too. Get yourself one of the above, a cheap USB vacuum cleaner. There are plenty available on Amazon
I’m hoping that doing this on a regular basis also increases the life of the machine as, while it is all backed up, it would be (will be?) a real pain when it finally gives up the ghost.
Have you considered opening up your machine to clean it? Do you have any tips on how to keep your PC in tip-top condition? Let us know!