Question Has anyone compared "blower" fans vs overhead fan effectiveness?

Mugsy

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I'm looking to get a new video card.

I've always preferred "blower" fans that blow air across the card and exhaust heat out the back of the computer vs "overhead" fans that blow straight down on the card (often with another card next to it blocking the fans) and dissipate the heat back into the case itself (so all other fans are now using heated air to cool.)

My budget does not allow for liquid cooling everything.

Has anyone performed a test comparing cooling fan configurations to see what works best? TIA
 
Centrifugal fans are high pressure, low CFM. Associated coolers are nice that they exhaust waste heat directly out the back of the card. The fan air is heating up as it goes down the length of the card though. So its efficacy is rapidly decreasing as it passes further into the heatsink.

Axial fans are low pressure, high CFM. Associated coolers benefit from much larger heatsink surface area to blow "fresh" air across. This is why you'll almost exclusively see axial fan coolers on GPUs with high(er) TDPs. You've also got the 120/140mm rear exhaust fan to carry heat out of the case, which has a high CFM as well.
 
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What works best is entirely dependent on the chassis and other cooling solutions.

A standard Micro ATX size chassis with only a single 80mm exhaust fan, and maybe a single intake fan (or none), then the blower style cards make a lot of sense. They become a major part of the system airflow.

If you have a chassis with multiple intake fans, a 120mm exhaust and/or top exhaust, you almost universally get better GPU cooling with an axial card.

The same decision style can be used to determine if the power supply should be part of the interior cooling system or not. That and carpet under the PC in the case of bottom mount power supplies.

You can also look at this in many ways. GPU temperature, System/CPU temperature, etc. Depends where you want to prioritize cooling. For most gamers, the GPU makes the biggest difference, so getting the most out of the GPU is desirable.
 
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Thx for the replies.

I haven't scouted a particular card yet, though I've been looking at 4060's which are just starting to become cheap enough to fit my budget.

At a later date (two years or so?), I will be considering an entire rebuild (since newer CPUs will need a new MoBo & RAM.) I'll probably get a new case to go with it. This starts running into a bit of money, so I upgrade "piecemeal" starting with a new GPU.

Right now, I have an air-cooled overclocked Ryzen 5800X (4.3GHz) with 16GB of DDR4-3600 ram. Reasonably high end by today's standards, but I'm still using an ancient GTX970 (exhaust fan style) and an 8 year old case with one 140mm intake fan in front, one 120mm exhaust fan in back & two on top (in addition to the GPU). Running temp is reasonably cool (never an overheat warning.)

I stagger upgrading my GPU & CPU every 2-3 years, and now it's the GPU's turn. 😉
 
(IMO) only really worth going with a blower card if you're building in an mITX case with limited airflow.

AFAIK, Nvidia is basically banning blower-style coolers from their board partners these days. So your decision is basically made for you.
 
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Interesting. I always thought "blower/exhaust" fan cards cooled better and case fans disrupted airflow hindering "overhead fans" ability to cool?

That's why I was wondering if anyone ever did a study.
 
Overhead fans can be disrupted if the air above them is blowing around in different directions, but a "blower" only has a side intake (the fan blades are never blown on by another fan except maybe in the desired direction.)
 
I did a Google Image search and I'm not seeing a single 4060 with "blower" style fan, but I do see a couple of 4070's and several 4090s.

Since I overclock using an air-cooled heatsink, a GPU with "blower" style cooler is probably the better way to go.
 
I did a Google Image search and I'm not seeing a single 4060 with "blower" style fan, but I do see a couple of 4070's and several 4090s.

Since I overclock using an air-cooled heatsink, a GPU with "blower" style cooler is probably the better way to go.
You're absolutely better off with the "standard" axial fan style heatsink.

Isn't PNY the only company that's released a blower style RTX4070? And only 1 SKU? Only available in China, cuz... reasons.


Side note: Not trying to steer you the wrong way, but since it's somewhat related to the discussion, I thought this was a novel idea
 
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A graphics card designer will pick the style of cooling that they think is appropriate to the cooler in question.
They will also include factors such as cost of the cooler and aesthetics.
Factory overclocked versions will need better cooling than the norm.

As to overclocking, realize that the chips are binned and the better ones are used in higher priced versions that can be sold for more.
You are not likely to get something for nothing.
If you need better graphics, buy a better card in the first place.

Whatever card you install, you will do better if you pay attention to the airflow through the case.
 
Blower vs. fan cooling systems have been compared for over ten years. It has been proven over and over and over again that a blower-style cooler is inferior. It doesn't cool the card as well and it sounds like a jet engine. The only advantage that a blower-cooler has is that it's usable in a tiny case that doesn't have enough internal air volume or flow to properly accept the heat from the card.

The best non-liquid cooling solution for video cards is the triple-fan system.
 
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