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question about blower fan gpu

I

inquisitor1

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Sep 23, 2023
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so its known that blower fan cards are not as desirable because of the 1 fan and the higher noise they make vs the 2 or 3 fan gpu

I was windering why they havent ever designed a blower fan with 2 or 3 fans? a 2 or ever 3 fan blower style gpu but wider then the 1-1.5 slot kind.

you can then run them all slower and less noise but air can be pulled in multiple spots to redirect from intake and shoot it 90 degrees out. less hot air in the case

1st fan at the edge takes the air and pushes it down the length of the gpu, then the other midway fan takes that air with the cooler air it pulled in pushes it out with a booster like effect

so I understand the 2-3 fan gpu push the air onto the cooler of the gpu but it all spills right into the case. near the cpu, near the ram. basically all over. doesnt seem efficient. seems to me that the gpu creates the most dispursed heat. the cpu usually has a cooler fan directed to the exhaust fan so they have a specific direction they push air while the gpu shoots it all over.

not sure why they never made a wide 2 fan blower fan instead. fans are bigger. 2 fans mean they dont need to spin that fast.
 
Centrifugal fans have one intake perpendicular to their exhaust. To use them as boosters requires relatively complex assemblies that I don't think are feasible at this small scale for gases. And don't forget that adding another fan means sacrificing heatsink area (because the accommodate the same axis).

I'm also not sure that having multiple fans would have that much effect on the noise. Resistance distance is already short so shortening it further may enter point of diminishing returns, yet the afore mentioned assembly adds extra resistance to be overcame. But most of all: Sounds may superimpose. The weighted sum of the noise your two slower fans could be louder than just one of them.
 
fe cards use a small cooler sandwhiched with 2 huge fans. I think its very well possible. adding a 2nd fan midway would be to help it along. like how a cooler like peerless assasin has 2 fans and a cooler in between. for certain can be done well. better design for getting air out of the case instead of the fans just pushing it on the memory, nvme and cpu. and thats what the cooler does.

the cpu cooler usually does its job by directing it towards the exhuast fan (except those horrible oem fan/coolers which spin it all over) but the gpu spreads it all over. its also huge so it spreads a lot of hot air. blower cards should be redisgned. they make the fans too small so they whine and whoosh more. I did hear mine when I ramped it up, but the size is the problem. make them bigger and wider and add a 2nd to help move the flow out better would be perfect. 2 larger fans at slower speeds always be less annoying then smaller fans which have a higher frequency to them.
 
It depends on the usage I guess.
I have used blowerstyle graphics cards before , and I can say that I am sensitive to unwanted noise.
If the card is power efficient and inaudible on idle, just working to display the desktop then it is OK by me.
When gaming there is usually a lot of sound coming from the game, so that doesn't bother me.
It blows heat out of the case, this means that casefans also need less RPM to cool.
It is when the GPU is crunching numbers that it can get annoying.
 
Founder's edition cards use axial fans, iirc. That's a different class from centrifugal ("blower") fans. Different structure, different operational principles, different performance characteristics.

One structural difference is that they have requirements for their "housing." Fans of both classes are already limited by the depth (shorter side of the plan's rectangle) of the PCB. And the blower housing needs its own space and gaps. So increasing the fan's diameter is not really an option (unless you want even bigger cards than these modern monstrosities).
 
inquisitor1 said:
so its known that blower fan cards are not as desirable because of the 1 fan and the higher noise they make vs the 2 or 3 fan gpu

I was windering why they havent ever designed a blower fan with 2 or 3 fans? a 2 or ever 3 fan blower style gpu but wider then the 1-1.5 slot kind.

you can then run them all slower and less noise but air can be pulled in multiple spots to redirect from intake and shoot it 90 degrees out. less hot air in the case
Click to expand...
I think the #1 reason for the companies is that such fans make cards more compact and easier to put nto a server case. They have no problems putting blower fans on professional/overpriced cards.
 
Jacky_BEL said:
It depends on the usage I guess.
I have used blowerstyle graphics cards before , and I can say that I am sensitive to unwanted noise.
If the card is power efficient and inaudible on idle, just working to display the desktop then it is OK by me.
When gaming there is usually a lot of sound coming from the game, so that doesn't bother me.
It blows heat out of the case, this means that casefans also need less RPM to cool.
It is when the GPU is crunching numbers that it can get annoying.
Click to expand...
well yea, it has to be done right but Im sure weve come some ways with improvements in thermodynamics and air flow/fan design. for certain can be done. those older style blower fans can get annoying if it needs to run fast and no audio is playing. when I was playing a game id blast it to protect the card but if you ever open up a gpu with one, they are puny and pathetic looking. im certain something better can be designed

I also think users didnt like the blower design because its old school and duh, 2-3 fans is better for cooling. and looks cooler

qxp said:
I think the #1 reason for the companies is that such fans make cards more compact and easier to put nto a server case. They have no problems putting blower fans on professional/overpriced cards.
Click to expand...
yes, I saw some moun them back to back. but im certain the old design can be improved upon. make them bigger, add a 2nd fan to help woosh it out faster towards the back. instead of 1 fan pushing it all through, where the air flow slows down, the 2nd fan boosts it out. like tag team

lets be honest, blower cards are ugly vs the beefy 3 fan design. I think that also impacted the design direction. but having 3 fans push all that air into the case means more fans to cool the case and more noise.....so thats a looped problem.

me? I just got a case with 6 fans included. and 3 more from the aio...and thats before the gpu. so thats at least 10 fans...

how can argue noise of the blower fan noise vs the other 9 fans? makes no sense. am I going to be using all those fans

hell frikin no. ill have 6 though...and thats not little 3aio 3 case.
 
I used the blowerstyle cards because that meant that it would fit in a OEM midsize case.

1740919463931.jpeg

I think this one is pretty cool looking.
Too bad I never came across the galactic empire edition.
 
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inquisitor1 said:
so its known that blower fan cards are not as desirable because of the 1 fan and the higher noise they make vs the 2 or 3 fan gpu
...
Click to expand...
The problem is not at all with the performance or noise of the blower fan. The current video cards problem is that the graphics chips are hyperoverclocked by the manufacturer.
I had video cards from HIS HD3870/HD4870 IceQ and noise and temperatures were quite low. In addition, they had great potential for overclocking.
HIS RX480(geniue AMD design) was already noisier. ASUS RX5700XT with blower fan was even louder and it practically does not overclocked.
We now live in the era of RTX5090 and poor engineering.
 
I think one of the reasons is the volume of the cooling solution needed with increased power demand.
Back in the day graphics cards started out with single slot width.
As long as power consumption on the cards is relatively low, one can get away with a single slot solution.
Some Nvidia quadro cards like the RTX4000 have a 160W TDP and are single slot.
The 1080Ti and Titan Xp had 250W TDP and had two slots width and was about the maximum the blower cooler could handle.
I guess cooling can increase with a three slot wide blower, but it will be a matter of diminishing returns.
The Titan Z had a 375W TDP and a triple slot solution, but it rejected part of the hot air back into the case.
Maybe nowadays it is more acceptable to have these big chunky graphics cards, and then blower style is not the best solution.
 
Jacky_BEL said:
I think one of the reasons is the volume of the cooling solution needed with increased power demand.
Back in the day graphics cards started out with single slot width.
As long as power consumption on the cards is relatively low, one can get away with a single slot solution.
Some Nvidia quadro cards like the RTX4000 have a 160W TDP and are single slot.
The 1080Ti and Titan Xp had 250W TDP and had two slots width and was about the maximum the blower cooler could handle.
I guess cooling can increase with a three slot wide blower, but it will be a matter of diminishing returns.
The Titan Z had a 375W TDP and a triple slot solution, but it rejected part of the hot air back into the case.
Maybe nowadays it is more acceptable to have these big chunky graphics cards, and then blower style is not the best solution.
Click to expand...
Actually, I don't think the volume is the problem. Intel and Nvidia (and maybe AMD) made server compute cards with power dissipation of 300W that are passively cooled. I.e. they have only a heatsink, no fan, and rely on the fans inside the case to blow air through. Also, think of notebooks - there are many that can dissipate as much as 65W inside a tiny case (compared to a desktop).
 
inquisitor1 said:
1st fan at the edge takes the air and pushes it down the length of the gpu, then the other midway fan takes that air with the cooler air it pulled in pushes it out with a booster like effect
Click to expand...
Except fans in "series" do not work that way. The second fan would not "boost" air flow unless it was spinning faster than the first to scoop up the air from the first fan. And then that second fan, because it must spin faster, would be making more noise. Move on to the 3rd fan and it has to move faster still and now you got the noise of a jet engine. The 3rd fan actually restricts the air flow of the 2nd and 1st fan. And the 2nd is restricting the air flow of the 1st. Not good.

Fans in series increases pressure, but not air flow.
Fans in parallel increases air flow, but not pressure.

The most efficient cooling occurs when more air flows.

Fans in series are good when both fans are working together to move air through a common heatsink. That is, where fan 1 is blowing into the heatsink and fan 2 is extracting air out of the heatsink - as seen in dual fan tower CPU coolers.
 
I'd say TDP is a big reason why we haven't seen much innovation on improving blower fan designs the power consumption of GPU's has really exploded upward in recent years. The R&D angle is another factor with companies being kind of lazy and stagnant on innovation and preferring to do more slow refinements over time. Companies are reluctant to take bigger risks. They could do something like quad M.2 cards have on GPU's with blow thru designs these days easily enough for like a 1 slot height blower on the top side of the PCB with a the bottom side having a more robust blower design. I'm not certain you'd gain much improvement on GPU cooling though. It might only improve it slightly by a couple degree's. It would however at least exhaust the heat outside which is beneficial for CPU and memory temps.

It would also help with cooling on anything on the rear of PCB or topside by having active cooling very useful in a clam shell memory design for example or if they were to do something like a dual GPU chip design where you have a inverted chip on each side maybe toss the tensor cores on it's own chip on the back for example, but that would require GPU makers innovating and being less complacent with their designs. It's a very real possibility except a unlikely one or not for another 10-20 years with how slow we see these things take shape even if the idea itself has merit.
 
Acer use a Compound Hybrid fan layout on their cards
 
inquisitor1 said:
so its known that blower fan cards are not as desirable because of the 1 fan and the higher noise they make vs the 2 or 3 fan gpu

I was windering why they havent ever designed a blower fan with 2 or 3 fans? a 2 or ever 3 fan blower style gpu but wider then the 1-1.5 slot kind.

you can then run them all slower and less noise but air can be pulled in multiple spots to redirect from intake and shoot it 90 degrees out. less hot air in the case

1st fan at the edge takes the air and pushes it down the length of the gpu, then the other midway fan takes that air with the cooler air it pulled in pushes it out with a booster like effect

so I understand the 2-3 fan gpu push the air onto the cooler of the gpu but it all spills right into the case. near the cpu, near the ram. basically all over. doesnt seem efficient. seems to me that the gpu creates the most dispursed heat. the cpu usually has a cooler fan directed to the exhaust fan so they have a specific direction they push air while the gpu shoots it all over.

not sure why they never made a wide 2 fan blower fan instead. fans are bigger. 2 fans mean they dont need to spin that fast.
Click to expand...
A card with 3 blower type fans would not have any space left for heatsink. When older cards use 1 blower fan it was placed at the edge, and heatsink was starting right after it. If you make them too small the need to spin even faster and 3 blower fans will sound like a real turbine.

Also this:
Bill_Bright said:
Except fans in "series" do not work that way. The second fan would not "boost" air flow unless it was spinning faster than the first to scoop up the air from the first fan. And then that second fan, because it must spin faster, would be making more noise. Move on to the 3rd fan and it has to move faster still and now you got the noise of a jet engine. The 3rd fan actually restricts the air flow of the 2nd and 1st fan. And the 2nd is restricting the air flow of the 1st. Not good.

Fans in series increases pressure, but not air flow.
Fans in parallel increases air flow, but not pressure.

The most efficient cooling occurs when more air flows.

Fans in series are good when both fans are working together to move air through a common heatsink. That is, where fan 1 is blowing into the heatsink and fan 2 is extracting air out of the heatsink - as seen in dual fan tower CPU coolers.
Click to expand...
 
Zach_01 said:
A card with 3 blower type fans would not have any space left for heatsink. When older cards use 1 blower fan it was placed at the edge, and heatsink was starting right after it. If you make them too small the need to spin even faster and 3 blower fans will sound like a real turbine.

Also this:
Click to expand...
It just creates turbulence which negates airflow
 
Last edited:
Jacky_BEL said:
Too bad I never came across the galactic empire edition.
Click to expand...
I had one. Still have the box lol. But the card itself died in a bad pc incident where I sheared some capacitors off the pcie edge by missing the socket, then botched the entire like an idiot thing trying to fix it by soldering. I really regret that day lol.
 
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