Case fan size question

[caernavon]

I think one of the case fans in my computer is dying (noisy, buzzy, etc). I didn't build the case myself -- I got it when I took a class -- and so I don't know what size fan to buy for a replacement. I looked a the fan and couldn't see anything marked on it. If I need to measure the fan to gauge its size, what should I be measuring -- the blade diameter? The distance between the installation screws?

[redwudz]

Usually just the width across the sides. Most case fans are 80mm (~3 1/8") The next common size is 120MM. And see what power connection it uses. Some use a 4 pin Molex, the same as the drives and others use a small 3 pin connector that goes to the motherboard. You can get adapters for both connectors if needed. I would also get a ball bearing fan. The cheaper sleeve fans don't last long.

Depending on your CPU and how much heat your system generates, you might want 2 case fans. One intake to the front and a exhaust to the rear. While you have the case open, this might also be a good time to blow all the accumulated dust out of there.

[kschang]

It it doesn't say, it's of the "standard" size.

[Cobra]

If all else fails, take a photo. We could probably tell from that. The common sizes are 80mm and 120mm, but you also get 92mm fans too - they're more rare, though.

[normcar]

Take the bad fan with you to the store (CompUSA, etc) so you can match it to a new fan. Also take the time to add all the fans that your case will allow. You can never add too many fans. The inside of your case will always be a few degrees higher than room temp even with many fans. Cooling the inside of your case will extend the life of your harddrives and other components.

[caernavon]

Take the bad fan with you to the store (CompUSA, etc) so you can match it to a new fan.

That's a good idea, thanks. I was just going to buy from Newegg as usual, but there's a MicroCenter right up the road