Case fans impact on GPU temps? Is this normal?

[RandomRolls]

I recently built my second PC and was curious about the impact of case fans and what the benefit they provide especially in a vertically mounted setup.

 

In my setup I have 5 (2x 140) intake and 7 exhaust, with the exhaust running slow, and case fans faster.

 

Testing with low speed GPU & high speed on the case fan. It seams like the fans on the GPU itself have more of an impact.

 

Are they there to just provide fresh air for the case in general? Is it normal for them to not have much of a performance impact directly on the part? 

[OhioYJ]

Depends on the case. Case fans can absolutely have a direct impact on cooling depending on the setup. In my last setup my GPU fans basically never turned on. Almost all the GPU cooling was provided by case fans. 

[RandomRolls]

1 minute ago, OhioYJ said:

Depends on the case. Case fans can absolutely have a direct impact on cooling depending on the setup. In my last setup my GPU fans basically never turned on. Almost all the GPU cooling was provided by case fans. 

Vertically mounted? 

[Alex Atkin UK]

8 minutes ago, RandomRolls said:

Vertically mounted? 

In this configuration the GPU fans and bottom case fans are technically fighting each other (if they are intake), so it would make sense that the case fans would have a huge impact on the GPU cooling when the GPU fans are off as they are pushing air directly through the fin stack.

[Agall]

7 minutes ago, RandomRolls said:

Vertically mounted? 

Just make sure those bottom fans aren't spinning fast enough to dead-head the GPU fans. Otherwise, yes, even vertically mounted, but you might want to limit their speed to not get weird turbulence or force air away from the dGPU's fans. 

[RandomRolls]

6 minutes ago, Alex Atkin UK said:

In this configuration the GPU fans and bottom case fans are technically fighting each other (if they are intake), so it would make sense that the case fans would have a huge impact on the GPU cooling when the GPU fans are off as they are pushing air directly through the fin stack.

They aren’t that’s my issue. When I turn off my GPU fans, and 100% my case / intake fans (5) the temperature stays the same and doesn’t drop noticeably. I don’t see the impact.
 

On my GPU the fin stack is completely covered in a plastic shroud. 

[PDifolco]

24 minutes ago, RandomRolls said:

I recently built my second PC and was curious about the impact of case fans and what the benefit they provide especially in a vertically mounted setup.

 

In my setup I have 5 (2x 140) intake and 7 exhaust, with the exhaust running slow, and case fans faster.

 

Testing with low speed GPU & high speed on the case fan. It seams like the fans on the GPU itself have more of an impact.

 

Are they there to just provide fresh air for the case in general? Is it normal for them to not have much of a performance impact directly on the part? 

I'd change that to more intakes than exhausts

Front Bottom side intakes (8)

Back and top exhausts (4)

I'm not sold at all on side case fans, you may stop them and see if they're not adding more turbulence than anything else

And the GPU would better benefit of the bottom fans in an horizontal setup

 

Edit : pretty nice BQ rig  

[Alex Atkin UK]

3 minutes ago, RandomRolls said:

They aren’t that’s my issue. When I turn off my GPU fans, and 100% my case / intake fans (5) the temperature stays the same and doesn’t drop noticeably. I don’t see the impact.
 

On my GPU the fin stack is completely covered in a plastic shroud. 

That's a bad designed GPU if they are only ventilating out the top, given only half the fin stack has a passthrough design, the first half HAS to ventilate up/down.  But yes, how obstructed the fin stack is on your GPU will make a huge difference.

[RandomRolls]

6 minutes ago, Alex Atkin UK said:

That's a bad designed GPU if they are only ventilating out the top, given only half the fin stack has a passthrough design, the first half HAS to ventilate up/down.  But yes, how obstructed the fin stack is on your GPU will make a huge difference.

My mount covers up most of it. 

[GuiltySpark_]

That's quite an odd airflow arrangement. Certainly not what I would have done.

[Blue4130]

6 hours ago, RandomRolls said:

They aren’t that’s my issue. When I turn off my GPU fans, and 100% my case / intake fans (5) the temperature stays the same and doesn’t drop noticeably. I don’t see the impact.
 

On my GPU the fin stack is completely covered in a plastic shroud. 

At idle, not surprising. The gpu clocks down to 300mhz and makes next to no heat.

[Alex Atkin UK]

On 2/9/2024 at 4:48 PM, GuiltySpark_ said:

That's quite an odd airflow arrangement. Certainly not what I would have done.

 

I'm still a traditionalist, front to back airflow as much as possible.  With a radiator, bottom to top.  The side panel fans seem kinda redundant to me, though may help the radiator but IMO would have them on a much lower setting than the rest to minimise turbulence.

 

Also what I dislike about vertical GPU is its going to pull air from the back ventilation, increasing dust.  Of course the plus is you eliminate the potential for GPU sad and given some models have issues cracking the PCB from the weight, this is a consideration.

My personal rig is inverted in an absolutely giant case, which seems to work well.  One consideration there is the vapour chamber on the GPU may work slightly less/more efficiently depending on orientation, although its hard to be sure without testing.