In cases that give the option to do so: power supply fan side up (intake inside) or down (intake outside)?

[Valentine]

I'm about to switch cases this week when I finally get a new motherboard (current mobo still works, just busted lan chip) because my pc sits underneath my desk and the bottom intake of the O11 Air Mini means unsually large amount of dust. Sure I could just not use the bottom intake but I have other reasons to switch back to my Meshify 2.

When I make the switch I'll be mounting my psu fan side up to take air in from the case because that'll mean one less filter I have to clean. The only real downside to this approach for me this that there might not be enough vent perforations (or hole to metal ratio as per Gamers Nexus parlance) on the psu shroud of the Meshify.

I feel that most people will prefer the former option than the latter, still I'm curious on the general opinion on this.

 

[TheinsanegamerN]

ALWAYS fan down to fresh air. Fan up will result in you both ingesting warmer air into the PSU (theres a reason modern cases have PSU air intakes) and you're fighting natural convection. If youre working the PSU enough to where the fan is spinning enough to collect significant dust, pointing it into the case is just asking for more noise, more heat, more bearing wear, ece.

 

[claes]

It really doesn’t make any difference. Pretty sure the spec calls for pulling air in from the chassis, but obvs cooler air is cooler

 

[joemama]

Seeing that you are running a 10900F with a 3080Ti, I would expect the air inside the case to be a lot hotter than outside, thus it would be better if the PSU can draw in fresh air.
Also the vent perforation doesn't seem better on the top side than the bottim side for Meshify 2 so the only concern would be dust.

 

[neatfeatguy]

I'm about to switch cases this week when I finally get a new motherboard (current mobo still works, just busted lan chip) because my pc sits underneath my desk and the bottom intake of the O11 Air Mini means unsually large amount of dust. Sure I could just not use the bottom intake but I have other reasons to switch back to my Meshify 2.

When I make the switch I'll be mounting my psu fan side up to take air in from the case because that'll mean one less filter I have to clean. The only real downside to this approach for me this that there might not be enough vent perforations (or hole to metal ratio as per Gamers Nexus parlance) on the psu shroud of the Meshify.

I feel that most people will prefer the former option than the latter, still I'm curious on the general opinion on this.

I think the best thing I did was get my case away from the floor and up higher, right now it sits on a file cabinet next to my desk, a good 30-36" above the ground.. Less dust/dirt/pet hair & dander the higher off the ground it sits. I also got some custom filters from https://www.demcifilter.com/ which are helping, too. I used to have to clean out the case every 6-8 months. After moving the case up higher and adding the extra filters, I rarely have to clean the case out. Last time I really cleaned it out was when I got my 5900X....which was about 2 years ago now and I had also gotten my filters at the same time. The only filter I really have to clean off is the one that sits below the PSU, all the rest stay pretty clean.

But with my 3080Ti taking a dump on me this past Saturday, I completely cleaned the case out again and the dust was minimal compared to the last time I had cleaned her out.

 

[claes]

Seeing that you are running a 10900F with a 3080Ti, I would expect the air inside the case to be a lot hotter than outside, thus it would be better if the PSU can draw in fresh air.

I’m just being pedantic here but one might argue that this is why having an exhaust near the GPU is beneficial

 

[TheinsanegamerN]

I’m just being pedantic here but one might argue that this is why having an exhaust near the GPU is beneficial

Aside from using a PSU as an exhaust being a very bad idea for said PSU, the GPU would be sucking up air from beneath it, then pumping hot air out the side where it would rise up. Putting the PSU fan up would, arguably, be stealing air from the GPU, not helping to cool it.

GPu exaust is most beneficial when it's a side exaust, old cases like the haf x still dominate GPU temperatures with modern cards.

 

[80251]

One argument against having a bottom mounted PSU intaking from inside the case: any dropped bolts, screws or nuts will tend to gravitate towards falling into the PSU. It's happened to me and tearing out and disassembling the PSU to get a loose screw was hardly my idea of fun.

 

[claes]

Aside from using a PSU as an exhaust being a very bad idea for said PSU,

It really isn’t — the ATX spec was designed for PSUs to intake chassis air and exhaust it. Any PSU worth its salt can handle warm air.

the GPU would be sucking up air from beneath it, then pumping hot air out the side where it would rise up. Putting the PSU fan up would, arguably, be stealing air from the GPU, not helping to cool it.

GPUs produce heat and spit it out everywhere. If a PSU fan is “stealing” air from the GPU you have intake problems, especially with modern designs where the fan only runs on high loads.

IDK what you mean about pumping air out the side unless you mean the PSU and not the GPU. Blower cards don’t really exist anymore.l for consumers.

GPu exaust is most beneficial when it's a side exaust, old cases like the haf x still dominate GPU temperatures with modern cards.

I’d be curious to see evidence of this. Not saying it’s not true, just haven’t seen any real tests beyond observational ones.

And please don’t get me wrong — all of my PSUs intake external air. I’m just being pedantic.

 

[Valentine]

I think the best thing I did was get my case away from the floor and up higher, right now it sits on a file cabinet next to my desk, a good 30-36" above the ground.. Less dust/dirt/pet hair & dander the higher off the ground it sits. I also got some custom filters from https://www.demcifilter.com/ which are helping, too. I used to have to clean out the case every 6-8 months. After moving the case up higher and adding the extra filters, I rarely have to clean the case out. Last time I really cleaned it out was when I got my 5900X....which was about 2 years ago now and I had also gotten my filters at the same time. The only filter I really have to clean off is the one that sits below the PSU, all the rest stay pretty clean.

But with my 3080Ti taking a dump on me this past Saturday, I completely cleaned the case out again and the dust was minimal compared to the last time I had cleaned her out.

Putting it on the table isn't really a viable option sadly, one it's just not my thing really, second at only 48 inches wide, my table is easily dominated by my 38 inch monitor. I actually wanted a nightstand-like height pedestal to rest the pc on. That way it isn't too low, yet not too high; just enough height to be at a comparable level to my table thus allowing me to use as a pseudo-extension of my table.

Table mounting becomes an option if I get a case like the Sliger Cerberus X, Sliger Trego, Jonsbo D41, SFF Time N-ATX V2.

 

[joemama]

Just stack the PC higher from the ground and the dusts would be greatly reduced

 

[Mussels]

This entirely depends on your PC setup and use case
I bought a PSU that only needs the fan on when the system is under heavy load, but i also run watercooling

So i have it facing down so leaks dont go inside it, and dust is not an issue


Cases that sit on the floor, or in dusty houses? God no, keep it inside facing up for that extra filtering. Heck some cases benefit from the extra airflow the PSU provides, pulling some heat out.