What's the deal with 92mm fans?

[Kaisersalsa]

All Jerry Seinfeld jokes aside, what is the deal with 92mm fans? I only ever really see them on stock case (like HP or Compaq, for example). I was looking for a water cooling system for the 92mm fan header and I was shocked to find that they don't actually exist. Are 92mm fans sub-optimal? I know 120mm is WAY more common but I can't help but wonder why there isn't support for it. Any ideas?

 

[ingtar33]

92mm was standard like 10 years ago.

they move solid air but they're very loud. you get quieter the larger the fan, so case makers drifted away from 92mm and 120mm became "standard", in the last 3 years more and more cases have been going to 140mm as standard, with some cases even squeezing 200mm fans into their construction.

in short, no you'll never find a 92mm radiator for a closed loop cooler.

 

[Gam3r01]

Cant get much clearer than this^
Old standard, now replaced by something larger and more efficient.

 

[Kaisersalsa]

92mm was standard like 10 years ago.

they move solid air but they're very loud. you get quieter the larger the fan, so case makers drifted away from 92mm and 120mm became "standard", in the last 3 years more and more cases have been going to 140mm as standard, with some cases even squeezing 200mm fans into their construction.

in short, no you'll never find a 92mm radiator for a closed loop cooler.

Wow. So, quick follow up, what are 92mm fans still being used in cases? Wouldn't it be more efficient, and maybe cheaper, to stock cases with 120mm instead?

 

[hwc1954]

I have a mini tower sized case. All of the stock factory locations (front intake, rear exhaust, power supply fan) are all 92 mm fans. I don't think a 120 mm fan would fit in the rear location. The 92mm fan and the I/0 panel take up the full width of the case.

 

[ingtar33]

[Wow. So, quick follow up, what are 92mm fans still being used in cases? Wouldn't it be more efficient, and maybe cheaper, to stock cases with 120mm instead?

well, dell and hp still use them as exhaust fans on many of their cheap business cases... they're also still used in mitx/matx format cases. so it's not like a market for them is gone completely. but finding them in a "normal" sized case is pretty rare

currently many people use 92mm fans for "spot" airflow, particularly hard core overclockers who are trying to keep airflow good over parts like ram or vrms, so there is some market for them

 

[hwc1954]

The differences are not that dramatic:

The Noctua high static pressure 120mm PWM fan moves 54 CFM (max RPM) at 22 dba noise. The Nocuta 92 mm PWM fan moves 47 CFM (max RPM) at 23 dba noise.

Clearly, bigger fans are going to move more air at lower rpms and be quieter overall, but we are not talking about orders of magnitude differences. A well-designed fan setup is going to have fully automatic temperature based fans at every location offering both quiet operation and max cooling as dictated by temperatures.

For spot cooling, Noctua makes an awesome little 60 mm fan and even a 40 mm fan that can be easily attached directly to heat sinks. I use one of the little 40 mm fans for Northbridge cooling on an AMD system. Northbridge chip runs hottest when the overall cooling is at low speed and less air is moving over the heatsink, so spot cooling is ideal. The temperature based fan actually slows down when the system heats up and the other fans are running fast.

As for the entire desktop market, I would think that small cases are a larger percentage than ever before. 20 years ago, almost all business/home computers were full ATX size towers. Now, that's a pretty rare size outside of the performance market.

 

[Findecanor]

Asetek has made 92mm all-in-one coolers that you can sometimes find on eBay.
Hardware Labs makes 1× and 2× 92mm and 80mm radiators for custom loops. Swiftech has a combined waterblock/pump and a micro-reservoir if you have restricted space for a custom loop.

For radiators you would want a fan with not just high flow (1.7 CFM = 1 mm³/H) but also high static pressure (mm H2O).
Strong 92mm fans are plentiful but finding 92mm fans that are both relatively quiet and have high pressure is the real challenge. The Noctua NF-A9 seems to be one of the best up to 2000 RPM. At least choose a PWM fan.

For CPU cooling in a slim case, using a cooler with a big fan directed at the CPU and cutting a hole in the side of the case for the fan intake might be a better custom solution.
Me, I'm trying to find a cooling solution for a slim vintage case that I don't want to desecrate by cutting open. :-\

Sorry for necroposting, but there isn't much info about this so I think it could be useful to someone who will search later.