Good specs for a system fan?

[devavictrix]

I recently upgraded my GTX950 to an R9 380 and it generates a lot more heat.

Given my only chassis cooling is a generic 80mm exhaust that came with the £20 case I thought id swap that for a 92mm fan and maybe put a couple of 120mm intakes on the side panel.

But when I started looking at chassis fans I realised its a can of worms full of rpm, Dba and cfm figures.

I guess like everyone else I want a good balance between Dba and CFM (I guess rpm is subsequent) but I don't know what a good benchmark fan would be.

Ive found a few 92mm fans that apparently shift 55-60cfm but at 35-40Dba, approx 3000rpm.
120mm fans are obviously better... 70cfm with 20Dba and 2000rpm are easy to find.

Are these figures quite typical or can you get 92 and 120mm fans that perform better with lower Dba scores? I should add that I don't want to spend much on new fans. I see some cost £15-20, or even more!

Thank you!

 

[zoltan.boese]

For the price of 3 case fans (£ 40-50), you can almost buy a new case. Or you can look for some budget fans aroud £ 8 each.

About the fan specs: cfm stands for air throughput, higher is better
rpm or rounds per sec is the (max) speed your fan can run at, to avoid high pitched noises, pick one under 1500rpm or one with a 4pin connector, so you can control the speed via motherboard
Unless you have a thick radiator or dust filter in front of the fan, pressure does not matter (mm/H20)
... and well noise measured in dBa - try and keep it under 30

And a good read: https://uk.hardware.info/reviews/5770/103-12cm-case-fans-review

 

[devavictrix]

Thank you for your reply.
I had a couple of 120mm fans from a gigabyte case and found a 80mm one in a bag of computer junk and have been playing all day!

I was surprised to find that the 80mm fan at 2800rpm was much louder than two 120mm fans going at 1000rpm. It created quite a draft too. If I ran CPU-Z stress test with just the cpu fan it hit 75c. With the three case fans going it hit 71c. So lots of noise for not a lot of reduction in temperature. I might try flipping the 120mm ones round and see if it makes any difference using them as an exhaust.

I'll see what it does to the graphics card temps next when its mining a cryptocoin. I would imagine the side fans will help a lot. It can go well over 90c when the case it closed up.

EDIT: All three case fans running at full speed takes a couple of degrees off.