Using PSU as intake

[Matt Elwood]

I've been brainstorming ideas for a small form factor build but a problem I'm having is how I'd effectively cool the GPU in such small cases such as the Fractal Nano S. The problem is with how the clearance between the GPU and the PSU would effect cooling. Does anyone have any comments on whether it would be a good idea to replace the PSU fan and mount it so that it intakes cool air from the back of the PSU and uses that to cool the graphics card. I feel like this is either a terrible idea or a stroke of genius aha.  

[OLS]

6 minutes ago, Matt Elwood said:

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Interesting idea at least! So in theory your thinking if you flip the fan inside the PSU and let's it spit the air from the back and up into the GPU?

[WWicket]

PSU is hot. The air won't be cool by the time it hits the GPU. Better to exhaust with the PSU.

[Mira Yurizaki]

I'm using a PSU as an intake, but it doesn't exhaust to anywhere directly (I think it actually blows right back out). Though I have dust filter to make sure any dust doesn't get in there.

[Matt Elwood]

6 minutes ago, OLS said:

Interesting idea at least! So in theory your thinking if you flip the fan inside the PSU and let's it spit the air from the back and up into the GPU?

Yeah, so I'd have the power supply mounted upside down with the fan on top. 

[STRMfrmXMN]

Get a blower-style cooler where the fan is a bit of a distance from the PSU. Boom, done.

[Matt Elwood]

7 minutes ago, WWicket said:

PSU is hot. The air won't be cool by the time it hits the GPU. Better to exhaust with the PSU.

It's not exactly scientific but i put my hand over the exhaust of my current PSU and it didn't feel too hot.

[Matt Elwood]

13 minutes ago, M.Yurizaki said:

I'm using a PSU as an intake, but it doesn't exhaust to anywhere directly (I think it actually blows right back out). Though I have dust filter to make sure any dust doesn't get in there.

Good point on the dust filter, I'm guessing I'd have to filter the intake somehow. 

[RadiatingLight]

35 minutes ago, WWicket said:

PSU is hot. The air won't be cool by the time it hits the GPU. Better to exhaust with the PSU.

 

27 minutes ago, Matt Elwood said:

It's not exactly scientific but i put my hand over the exhaust of my current PSU and it didn't feel too hot.

 

Kinda.

Looking at jonnyguru testing of PSUs (specifically the Seasonic Prime 1000W, since it was the first link I clicked on) shows that at the full 1000W load of that PSU, the intake temperature was 29c, and the exhaust was 41c.

41c is hot, but definitely colder then air in a SFF case that has been recirculating for a while.

[pzspah]

You could just get an SFF PSU for 2cms more clearance and call it a day.

[WWicket]

Just now, RadiatingLight said:

 

 

Kinda.

Looking at jonnyguru testing of PSUs (specifically the Seasonic Prime 1000W, since it was the first link I clicked on) shows that at the full 1000W load of that PSU, the intake temperature was 29c, and the exhaust was 41c.

41c is hot, but definitely colder then air in a SFF case that has been recirculating for a while.

It is moving the same amount of air through the case (roughly) regardless of whether it is an intake or exhaust (you aren't going to get 'that big' of pressure differential inside the case). As an exhaust, warmer air is moving over the PSU and the PSU will get less cool-- np. As an intake, warmer air will be moving over the gpu and the gpu will get less cool. It might not be a huge difference, but it will be worse. Probably. Easy to test it... install the psu normally, check gpu temp., then flip the psu fan and check gpu temp.

[Mira Yurizaki]

9 minutes ago, WWicket said:

It is moving the same amount of air through the case (roughly) regardless of whether it is an intake or exhaust (you aren't going to get 'that big' of pressure differential inside the case). As an exhaust, warmer air is moving over the PSU and the PSU will get less cool-- np. As an intake, warmer air will be moving over the gpu and the gpu will get less cool. It might not be a huge difference, but it will be worse. Probably. Easy to test it... install the psu normally, check gpu temp., then flip the psu fan and check gpu temp.

It's not going to be such a huge difference for it to really worry about though. A 1000W PSU at 100% load only blowing out 41C? I'm pretty sure it's going to be a lot less for a typical single card gaming rig pulling at worst 300W on a 600W PSU (assuming the same build quality on the PSU)

[WWicket]

Just now, M.Yurizaki said:

It's not going to be such a huge difference for it to really worry about though. A 1000W PSU at 100% load only blowing out 41C? I'm pretty sure it's going to be a lot less for a typical single card gaming rig pulling at worst 300W on a 600W PSU (assuming the same build quality on the PSU)

I agree. It probably won't make enough of a difference either  way to matter. So why bother switching it?

[WWicket]

Duplicate post.

Edited June 12, 2017 by WWicket
Duplicate post.

[RadiatingLight]

5 minutes ago, M.Yurizaki said:

It's not going to be such a huge difference for it to really worry about though. A 1000W PSU at 100% load only blowing out 41C? I'm pretty sure it's going to be a lot less for a typical single card gaming rig pulling at worst 300W on a 600W PSU (assuming the same build quality on the PSU)

it is important to note that the 1000W unit referenced was an 80+ Platinum PSU, but still, 95% efficiency on 1000W is more heat than 92-88% efficiency at 350W

[Matt Elwood]

55 minutes ago, RadiatingLight said:

 

 

Kinda.

Looking at jonnyguru testing of PSUs (specifically the Seasonic Prime 1000W, since it was the first link I clicked on) shows that at the full 1000W load of that PSU, the intake temperature was 29c, and the exhaust was 41c.

41c is hot, but definitely colder then air in a SFF case that has been recirculating for a while.

That's pretty good to hear, especially considering where i live the intake temp will be closer to 20c. And, 41c is around half the temperature GPUs can get to so it should be cooing it down for the most part. Thanks for the help

[pzspah]

Pardon the low quality photo [and the cablerouting mess], my phone is a potato.

 

The 1060 in this pic is 4cm tall and clears the SF psu by 3cm giving it alot of room to breathe. Off the top of my head most ATX psus are 2cms taller.

 

Only downside is that you need to get extensions for the two powercables going to the motherboard and an ATX to SF adapter. The cheapest adapter I found was a kingwin for $6 on ebay.

 

Jonnyguru has a review on the SF600 and some other SFXs, the former appeared to be the best one though.

 

Now I'm off to turn off that rgb which I never knew was on.