PSU up or down?

Mull3t

Mull3t

Mull3t

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Joined
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Leicester
Right, first step of the build and I'm not stuck but more just want to be sure. On the case I have (Asgard Pro) they is a ventilation mesh for the PSU fan to face down (so pulling air from underneath the case) the case also has about half inch lift from the floor.

My question is my tower is going to be sat on the floor on carpet, surely this will restrict air floor somewhat? Or am I being paranoid?
 
It's normally OK, on carpet it can get a little warmer than on a cooler surface (3-5 degrees I predict), however I normally have the PSU facing up for the aesthetics.
 
Mull3t said:
Right, first step of the build and I'm not stuck but more just want to be sure. On the case I have (Asgard Pro) they is a ventilation mesh for the PSU fan to face down (so pulling air from underneath the case) the case also has about half inch lift from the floor.

My question is my tower is going to be sat on the floor on carpet, surely this will restrict air floor somewhat? Or am I being paranoid?
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Just because your paranoid doesn't mean the government isn't out to get you. :D

In this case, unless you find a way of raising the chassis up a couple more inches or so, I would just have the fan facing up.
 
Carpet isn't going to damage the PSU (I assume it's not 50 years old and failing apart) the fan isn't going to be strong enough to clean your carpet. :)

Also you'll probably get way more dust coming in the rest of the case from other case/psu fans and falling down into your PSU, as most of the dusty air in your room is going to be above foot level. Once dust has settled under you case it's likely to stay there, only dust in the air tends to get into your case.

Face down is the ideal way to have the PSU mounted, and the reason why the case has a ventilation mesh.

Since heat rises you fan will be trying to counteract thermal dynamics (and it won't be very successful at this, as it's not been designed to run that fast). So a lot of the heat will rise into the rest or your PC, rather than being vented out of the back of the PSU.

Easy way to show this, put your had above the PSU when you are benching for extreme power use and if you feel any temperature difference the PSU fan isn't running fast enough to counteract thermal dynamics.

As far as I'm concerned the only reason to have the fan face up is if the case you have would completely block it off. Mostly likely this would be an old or cheap case as most of these designs have been mothballed.
If I had a case like this I'd bin it or use it on a cheap non-gaming system only.

So don't switch, it's definitely not the safe side unless you want the PSU nicely insulated with case dust. :P
 
It's not so much I am worried about the PSU sucking in dust but more that the minimal space will not get enough air flow through and potential to overheat.

Here is my rig sat on the carpet, as can see it's virtually no space (maybe just under 1cm).

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HalfBakedJake said:
I used a thin piece of slate for my Dad's PC. Cut to the width/depth of the case. Looks really smart.
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This or cut a piece of MDF the same size as the bottom dimensions of your case. You could even spray it black to make it look even better against your case.

Mine is a bottom facing case/PSU set up but mine is in a desk. That i built out of a Welsh dresser some time back. Looks really smart i might add :D
 
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I have my PSU facing down, sucking in from the bottom. I have about the same clearance as you do - shouldn't be a problem at all for it to suck up all the air it needs... Remember it is AIR we are talking about here, not water or treacle lol - air flow via a PSU fan is not going to be restricted by a 1cm gap.

But yes, sitting the PC on top of a board will of course give you a bit bigger gap due to the case feet not sinking into the carpet slightly.
 
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