The NVidia 3080 FE and 3090 FE Cooler design. Will no one think of the CPUs!

Snowdog

[H]F Junkie
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After seeing the airflow of the new cooler, there have been some some online concerns about it overheating CPUs.

But this is NOT a cause for concern. Lets think about this from perspective of a standard PC case using just the exhaust behind the MB, and examine some points it raises.

1: Close to 100% of the heat from an open air cooler has to exhaust through that exhaust behind the CPU cooler anyway. So if the new cooler flowed all the hot air into the path of the CPU, it wouldn't really make difference once the system is heat soaked, all that heat is exiting the case essentially through the cooler anyway. So worse case we should be looking at neutral.

2: This new cooler dedicates one fan to blower card operations. So some significant portion of that heat is directly exiting the case. This is pure win. This is the biggest benefit of the design. It's a partial blower. With some portion of the heat leaving through the blower, less will be going through the CPU. This design should lead to cooler CPU than a traditional open fan cooler. For CPU temps. Blower < New NVidia Half Blower < Traditional Open Fan cooler.

3: Blowing air through the GPU Cooler, into the path of the CPU is NOT new. Several cards did this before, several of the AIB 3000 series are doing it. It just never got attention before, and these design don't have the advantage of working like a partial blower.

This is not a problem, it's a solution:
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At least SOME of the hot air is being vented out the back. With the AIB designs, doesn't it just blow the hot air around in the case to be vented anyway?
 
At least SOME of the hot air is being vented out the back. With the AIB designs, doesn't it just blow the hot air around in the case to be vented anyway?

The issue is that the hot air is exhausting directly over the cpu and its cooler. Anyone with a rudimentary understanding of thermo dynamics knows that has a lot more impact than just ambient hot air.

Will it be a problem? depends on how much air the rear fan exhausts, but given the high power of these cards I wouldn't be surprised if people need to redesign their airflow, much like they need to reconsider power supplies.
 
Admittedly, I initially had bad preconceptions of how it might perform with air coolers as well. However after seeing posts from Kyle, you, and a few others, it does indeed seem to be a solution and not a problem.

I was even thinking about buying a new case and an AIO for my CPU, but I'm sure it will work rather well with my setup. Here's to hoping the acoustics aren't bad...
 
Admittedly, I initially had bad preconceptions of how it might perform with air coolers as well. However after seeing posts from Kyle, you, and a few others, it does indeed seem to be a solution and not a problem.

I was even thinking about buying a new case and an AIO for my CPU, but I'm sure it will work rather well with my setup. Here's to hoping the acoustics aren't bad...

Definitely echo the sentiments on the acoustics. The best cooling design ever is worthless to me if its as loud as a hairdryer.
 
It works especially well in cases that vent most of their heat out of the top. I really like the design.

Yep, I have a Corsair 600T with a 200mm top exhaust. I also have my CPU AIO setup to pull cool air in from outside the case and exhaust hot air through the top. The Ampere FE design fits right into that flow.
 
Better have good case air flow.
I might have to go back to my old case if temps are bad in this one.
It may not be as bad as it seems tho depending on the case.
 
Those aircooled CPUs will really suffer. Maybe a lot of roasted 10900Ks soon...

Roasted from what?
Manual voltage settings way past the safe zone and degrade as fast as possible?
Disable all thermal shutdown behavior to demolition derby the cpu?

Ambient swings from 0c to 50c aren't uncommon in my area over the course of a year.
Add a closed room slowly heating up from a build and that detonates my PC?
 
This is a none issue. With the majority of air being kicked out the back I don't expect much difference from any current high end gpu that dumps inside the case where it still gets suck through the heatsink. People just try to find issues in everything.
 
This is a none issue. With the majority of air being kicked out the back I don't expect much difference from any current high end gpu that dumps inside the case where it still gets suck through the heatsink. People just try to find issues in everything.

I too suspect this is overblown (hah) but I'd like to see actual thermals and noise for this new cooler.
 
I too suspect this is overblown (hah) but I'd like to see actual thermals and noise for this new cooler.
No doubt but I actually don't care since w/e I decide to buy it is going under water. I want to get a 3090 but I might have to get a new PSU too.
 
And for the 3090 they said "10x quieter" than the RTX Titan. An interesting claim to say the least (RTX Titan can't have been very different from 2080 TI FE noise wise). It's a really big heatsink at least, that should help combined with the new design.
 
Honestly if you are buying 700-1500 cards and not putting a water block on you are doing it worng...
 
Honestly if you are buying 700-1500 cards and not putting a water block on you are doing it worng...
Or getting it with one? If they're coming with 240mm AIOs (EVGA at least), should work pretty well IMO.

Those aircooled CPUs will really suffer. Maybe a lot of roasted 10900Ks soon...
Do you imagine the GPU being ducted exclusively to the fan intake of an HSF? I can see it making a bit of difference, maybe the CPU fans spin up a bit more in response, or worst case the CPU has to throttle a bit sooner, but not 'roasted'.

Certainly something to keep in mind when laying out ideas though. Those 'dual chamber' enclosures make a bit of sense when you have two ~300W parts and could potentially segregate the heat from each and provide each with fresh / cold intake air!
 
Also 50C is 122 degrees F soo...yeah. I suspect some exaggeration going on. ;)

No, we have wildfires in the SF Bay Area right now.
City blocks burning down in your county is becoming a yearly event.
The highway melted not far from me last week.
 
Those aircooled CPUs will really suffer. Maybe a lot of roasted 10900Ks soon...

The point of the original post, was to try and clear up exactly that misconception. Even if all the new cooler did was blow the heat into the vicinity of the CPU cooler, it wouldn't have that effect.

In a typical PC case, there is one exhaust. It's behind the CPU cooler, so all the heat MUST eventually exit through there, which essentially means it's exits through the cooler.

So in the long term, the same amount of heat exiting the box in the same place (through the CPU cooler), will raise CPU temperature the same amount.

While it might be initially intuitive to think blowing GPU exhaust in that direction will overheat the CPU, but that is wrong, when the heat really has no where else to go.

That's major point #1. This does not cook CPUs even if you blow GPU heat right in front of the CPU cooler. Because all the heat has to go through there anyway... There is no way to keep the GPU heat from the CPU.

Major point number #2. The Fan near the bracket works as in a blower card, directly exhausting a significant portion of the GPU heat directly out of the case. Meaning less heat build up in the case, and thus LESS heat reaching the CPU. So this design results in cooler CPU, not a hotter CPU. While a pure blower card would give you a cooler CPU, a typical Open Air card will give you a Hotter CPU. The NVidia FE design will give you a cooler CPU than an open air card.

This design is a partial blower. It will keep your Case/CPU cooler than open air GPU coolers, but not as cool as full blower GPU coolers (but it will cool GPU much better than normal blower coolers).
 
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I just saw this video today that further explains nvidia new flow through concept. I don't know why he spent quite some time in the video talking about having RTX 3080/3090 in ITX case as the mid-tower/compact and perhaps full tower case are more popular PC cases in the market.
 
The point of the original post, was to try and clear up exactly that misconception. Even if all the new cooler did was blow the heat into the vicinity of the CPU cooler, it wouldn't have that effect.

In a typical PC case, there is one exhaust. It's behind the CPU cooler, so all the heat MUST eventually exit through there, which essentially means it's exits through the cooler.

So in the long term, the same amount of heat exiting the box in the same place (through the CPU cooler), will raise CPU temperature the same amount.

While it might be initially intuitive to think blowing GPU exhaust in that direction will overheat the CPU, but that is wrong, when the heat really has no where else to go.

That's major point #1. This does not cook CPUs even if you blow GPU heat right in front of the CPU cooler. Because all the heat has to go through there anyway... There is no way to keep the GPU heat from the CPU.

Major point number #2. The Fan near the bracket works as in a blower card, directly exhausting a significant portion of the GPU heat directly out of the case. Meaning less heat build up in the case, and thus LESS heat reaching the CPU. So this design results in cooler CPU, not a hotter CPU. While a pure blower card would give you a cooler CPU, a typical Open Air card will give you a Hotter CPU. The NVidia FE design will give you a cooler CPU than an open air card.

This design is a partial blower. It will keep your Case/CPU cooler than open air GPU coolers, but not as cool as full blower GPU coolers (but it will cool GPU much better than normal blower coolers).
The temperature increase of air going into an air cooler for the CPU depends on a lot of factors. How much mixing of cooler air with exhausted GPU air, air flow and temperature from the GPU, power of the GPU, case design, air flow and direction, fan speeds, locations etc. So many variables. Just take a look at your GPU, put a fan on it in the back and see how very close it would be to these tall big vertical CPU coolers, it will be right up next to it!

Here is a Treadripper system 3960x with a BeQuiet air cooler, look at the EVGA 1080Ti which is probably not that much shorter than a 3080 and put a fan on the back of it right at the suction of the CPU air cooler. If the GPU heats up the air 10c, where is that air going to go? Next is the CPU cooler will also be partially blocking the GPU fan, restricting GPU airflow, less cooling to the GPU. Until this is measured it is just theoretical to a point but it is very obvious this can pose problems with CPU air coolers, certain configurations etc. and possibly performance of the GPU due to restricted air flow. Next is ram, if you like OCing ram beyond XMP, heat will make it much more difficult, something else to look at. The previous cards that blew out the back of the GPU where much lower power as in less than 200w cards and not 320w+ ones. It will be interesting to see how this design with the given power envelope succeeds or not.

AirCoolerVideoCard.jpg
 
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The best solution above with that sort of configuration is to reverse the CPU fans and have the back case fan blow into the case to the CPU cooler, with the CPU cooler exhausting at the end of the GPU. The ram will become the potential issue after that. Exhaust the air on top or the front of the case. I think that would work, now the GPU restrictions caused by the CPU cooler interference is another matter. On this motherboard using the second PCIe 16x Gen 4 slot is an option to eliminate that, X570 and Intel motherboards the second PCIe slot are 8x which can have it's own restrictions.
 
Those using two 3090's with NVlink to double up the ram will have a real treat, the exhausted hotter air from one will go right through the second card :eek:. The two fans in series may help each other to pull more air through, still the one receiving the hotter air will, well run hotter. How much is another thing at 100% gpu usage.
 
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This is a none issue. With the majority of air being kicked out the back I don't expect much difference from any current high end gpu that dumps inside the case where it still gets suck through the heatsink. People just try to find issues in everything.
Regular video cards exhaust up and out, bottom and out (edges on the card) and mixes with colder air from the case fans. Take one part 10c hotter air and mix it with 10 parts cooler air from the case fans and you get only slightly higher temperature overall going into the CPU HSF. Now take that 10c one part hotter air volume, do not mix it with colder air and dump it right into the CPU HSF. Yes all the heat comes out of the case the same way but what the CPU HSF will have is much hotter air going through it and not mixed with the colder air. It is like exhausting all the heat from one GPU, warming up the air and then using that same hotter air to cool the second GPU, the second GPU will run much hotter yet still the same amount of heat will come out of the case. How heat is transferred can be very much different for the same amount of heat removed.
 
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It's going to vary wildy from one build to another. I would understand the concerns if all I had was a 92mm back exhaust fan.

But with top exhaust? I'm pretty sure it can only help. Especially if the blow-through-the-card fan is pressure optimized.

In my personal case (Define Nano S) , a bottom 150mm Noctua pushes air towards the top of the case and a good portion blows past the GPU up to the CPU (helped by the fact the FE is of the narrower cards). Feeds the GPU good too then you add the 140mm bottom front intake fan.
Then it gets interresting. Being ITX, the fan blows its air not on the RAM but past it, and since the GPU is considerably higher in the build, the air it exhausts is very close to the top of the case (pulled out by 2x 140mm up top). Finally, that hot air is not only pulled out the top, it's also mixed with the air coming in from the top front 140mm pushing towards the GPU.

If I manage to get my hands on one I will definitely test it. Also curious what the difference would be if one were to channel that air straight to the top (relatively easy since it's already so close to the top).

I only question the acoustics.
 
That is the key, it just needs to be tested out for real data. Looks like a potential problem, maybe it could be for certain configurations. Until tested it is mostly guesses while it may look obvious best to get real data.
 
I for one am worried about the straight through exhaust... I have a PETG tube that runs right above where that hot air will exhaust. And that air can get pretty hot, so while it may not cause alarm immediately... repeatedly being blasted with hot air then cooled down... it will essentially be a hot air gun on low setting.

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I for one am worried about the straight through exhaust... I have a PETG tube that runs right above where that hot air will exhaust. And that air can get pretty hot, so while it may not cause alarm immediately... repeatedly being blasted with hot air then cooled down... it will essentially be a hot air gun on low setting.

??? How do you think the heat gets out of your case with you current GPU?

Why do you think there is any less GPU heat interaction with your CPU cooling system, than with different fan arrangement of the FE cooler?

If you are worried about it. Get an AIB card with a closed back. It won't help though, and probably make things worse.

Same heat has to get out of your case either way and it is going to go past your CPU cooling either way.

Well except that the FE cooler is a partial blower and some of the heat escapes directly out of the case, bypassing interaction with your CPU cooler, and is in actuality the better system for keeping your CPU cooling.

Though in reality the differences will probably be margin of error measurement for CPU temps in tower cases.
 
??? How do you think the heat gets out of your case with you current GPU?

Why do you think there is any less GPU heat interaction with your CPU cooling system, than with different fan arrangement of the FE cooler?

If you are worried about it. Get an AIB card with a closed back. It won't help though, and probably make things worse.

Same heat has to get out of your case either way and it is going to go past your CPU cooling either way.

Well except that the FE cooler is a partial blower and some of the heat escapes directly out of the case, bypassing interaction with your CPU cooler, and is in actuality the better system for keeping your CPU cooling.

Though in reality the differences will probably be margin of error measurement for CPU temps in tower cases.

While the heat generated by everything in the case is already substantial, I agree, I’d argue that having a fan now blowing hot GPU air directly at the tube is a little worse and cause for concern.

My concern is the PETG warping over time, now that it’ll have a mini hot air gun blowing on a specific part of the tube for hours while I game.

I really want that FE card though...not a AIB. The FE looks sexy, guess we’ll see.
 
My concern is the PETG warping over time, now that it’ll have a mini hot air gun blowing on a specific part of the tube for hours while I game.

I think you are imagining things that aren't happening. You have a either a open air card, partially recycling in it own heat and rising it exhaust temps even higher, and have them waft up more gradually, but again HOTTER. Or you have a fast moving but cooler air stream flowing through the FE cooler. Either way they aren't concentrated source, and they both mix with the front intake air. Neither one is cooking your pipes, both strategies place the same heat load on the box.
 
Honestly if you are buying 700-1500 cards and not putting a water block on you are doing it worng...

Wha......? Please explain how just plug and play has been wrong for a lot of us who just don’t wanna disassemble and mess with water cooling. You elitist Piece of sh....... Um excuse me I meant you big BIG meanie!
 
I think you are imagining things that aren't happening. You have a either a open air card, partially recycling in it own heat and rising it exhaust temps even higher, and have them waft up more gradually, but again HOTTER. Or you have a fast moving but cooler air stream flowing through the FE cooler. Either way they aren't concentrated source, and they both mix with the front intake air. Neither one is cooking your pipes, both strategies place the same heat load on the box.
This just really needs to be tested. Agree if the air flow is higher through the FE, lower the temperature on the exhausted air from the card. The straight through fin design looks great for air flow.

The mixing of cooler air with warmer air inside the case before it cycles through another component like a CPU cooler can be very significant. Running SLI with fan cooled cards can have 10c plus hotter tempertures on the upper card since the bottom card is heating up the air reaching the upper card.

If I can get a hold of a 3080 I can do some tests, see how much air from the 3080 goes into the CPU air cooler, any temperture effect etc.
 
Do we think those with top mounted radiators as an exhaust will be ok?
I would think so, maybe fan to cool the ram as needed depending upon how hot the 3080/90 card exhaust air gets -> the card exhaust air could aid in cooling the ram by having air flow over then as well. I could see custom fan curves that are set too low which would allow the air to get hotter exhausting from the card which possibly could cause an issue but that would be user error. Higher the fan speed, more air flow, less the increase temperature from the exhaust air from the card.
 
While the heat generated by everything in the case is already substantial, I agree, I’d argue that having a fan now blowing hot GPU air directly at the tube is a little worse and cause for concern.

My concern is the PETG warping over time, now that it’ll have a mini hot air gun blowing on a specific part of the tube for hours while I game.

I really want that FE card though...not a AIB. The FE looks sexy, guess we’ll see.
No, it won't be any different. As mentioned, a "normal" card just takes the heat and cycles it a few times before it has to be exhausted. This air that's been heated more than once is hotter than fresh air that only goes through once. It's removing heat from your case more quickly instead of having it recycle around. Also, your PETG shouldn't be an issue unless you run out of fluid and your pump stops... if that happens I don't think the biggest worry is going to be how quickly the PETG might deform, but WTF happened to all my coolant?!!?!? If you want to do a test, put some small tubing in your sink and run some ~ambient water through it while you hit it with a hair dryer. With the water flowing through, it's not going to get hot, if it does, replace your faucet and try it again ;). Anyways, the air coming out will be slightly cooler than it is now anyways, so if it was going to deform, it would already be doing so. The heat load won't change, just the rate at which that heat can escape changes. If you more quickly dispel of the heat, then you will have lower temps inside your box overall (but it will heat up your room all the same).
 
Those using two 3090's with NVlink to double up the ram will have a real treat, the exhausted hotter air from one will go right through the second card :eek:. The two fans in series may help each other to pull more air through, still the one receiving the hotter air will, well run hotter. How much is another thing at 100% gpu usage.

Well... if you’re spending $3,300 on cards maybe 3d print a $10 baffle? lol. Or look for a different design.

While the heat generated by everything in the case is already substantial, I agree, I’d argue that having a fan now blowing hot GPU air directly at the tube is a little worse and cause for concern.

My concern is the PETG warping over time, now that it’ll have a mini hot air gun blowing on a specific part of the tube for hours while I game.

I really want that FE card though...not a AIB. The FE looks sexy, guess we’ll see.

I think people are greatly exaggerating the exhaust temp. PETG has a Tg of around 90C? The air should be no where close to that. If your card is running at 65C the exhaust air is probably 35-40C? These fans look high flow. I don’t think the delta T is going to be too crazy.

Overall I love the FE design and will probably snag it. A 3 slot card that exhausts half the air is half way to my dream of a four slot blower. But if it doesn’t fit your application there will be a billion different coolers to choose from.
 
Well... if you’re spending $3,300 on cards maybe 3d print a $10 baffle? lol. Or look for a different design.



I think people are greatly exaggerating the exhaust temp. PETG has a Tg of around 90C? The air should be no where close to that. If your card is running at 65C the exhaust air is probably 35-40C? These fans look high flow. I don’t think the delta T is going to be too crazy.

Overall I love the FE design and will probably snag it. A 3 slot card that exhausts half the air is half way to my dream of a four slot blower. But if it doesn’t fit your application there will be a billion different coolers to choose from.
That is what I am thinking, only problem is if someone sets the fan speeds rather low at high GPU loads. User error. Just all needs to be tested and confirmed. If the delta T is low it could actually aid cooling to ram and VRMs :D. Presently on the 3960x system, the CPU air cooler heats one side of the Ram hot to the touch due to the exhaust from the cooler, two sticks cool, two sticks hot. The 3080 maybe able to get those hotter ram sticks cooler. I will be going to water cooling the CPU anyways once it gets put into the case, waiting on an Artic cooler for the 3900x which will be put in another case. Could be or could not be a problem with CPU air coolers, looks like the CPU air cooler may restrict the GPU exhaust air as a note.
 
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