I'll probably need to replace my CPU fan soon, because it's obviously failing. It's slower and less steady, and I haven't heard a fan make so much noise since the decades-old exhaust fan in my bathroom died. How hard is it to select a replacement fan?--this will be my first time. Can I expect any fan to work if it is a good brand and the right size, or is it more complicated?

It's the fan that came with the CPU, so I'm not surprised that it's failing after only sixteen months.

Ahh, it's fine, really pretty trivial. Very uncommon to replace only the fan though, you'd get a single unit of the heatsink and fan. Assuming nothings changed since I last did it, just remember that the clips on the CPU are quite strong, and you might need a decent screwdriver to push it down with a reasonable amount of force. Many don't need toosl though. And as long as the thermal paste / pad goes on it the right place, there's really nothing to worry about.

Good makes? Akasa was always a good mid/high range brand among others. Oh and Zalman.

Well, if it comes with a heatsink, fine, I guess; but there's nothing wrong with my heatsink...

Well in theory fans are designed to work with certain shaped sinks etc... and also there's no guarentee you'll be able to directly swap just the fan and get a good tight fit with it... certainly harmless trying that much.

You can get a lot of information googling "heat sink fans" and you can buy just the fan but the problem is if you buy online making sure you get the exact right size. Take the old one in when you go to your local shop.

Old PCs are fun to learn on.

Never hesitate to bust out the alternative-engineer in you.

(by that I mean, it's a fan, it should be held on by duct tape, and that achieves the goal, right?)

Yes, there is, its got a crap fan attached to it.

A heatsink tends to be designed to mount correctly to a particular fan (there are a few which are sold without fan and take a standard xx mm fan, but that's the exception) so you might find that just swapping the fan gives you a situation in which more of the airflow doesn't go through the heatsink.

You don't say which processor type it is; the heatsink/fan combos tend to be for one particular socket type. And (obviously) it needs to be able to cope with the heat; not only are some processors hotter than others, if you do something like overclocking you need to be able to move more heat.

Getting this right depends on priorities; mine are for a PC that doesn't sound like a hovercraft at take off, so that pushes me towards quiet combos, but your priorities might be different.

OE fan/heatsink combos tend to be designed down to a price and that does little for silence (and maybe longevity...as you have found) and, along with Zalman (already mentioned) who have some real enthusiast products, I would add Arctic Cooling who do some good, mid-range, 'overclocker' products without being either ridiculously expensive or loud.

Usually, by the way, the enemy of all things cooling is dust, so if your PC is in a dusty environment, maybe it needs more attention to preventative maintenance.