What's with PSU's almost all being at the bottom? Bad idea for water cooling, no?

undertheradar

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I've noticed that most current mainstream cases seem to mount the PSU below the motherboard. I'm guessing that this is so the PSU doesn't have to suck in warmer air and the CPU can hang out in the warmer air instead? I read that power cables might seem easier to route from below (shorter), but are they really? I mean, who skips running everything behind the mobo first, right?

Then there are the more "cube" cases where the PSU sits in its own chamber behind the mobo, but I really would prefer something narrower to take up less space on the desk.

Having the PSU at the bottom of the case seems like a bad idea for anyone doing water cooling where any leak around the CPU, mobo, or GPU can drip right into the 120Vac bits and cause big zappy zaps. I thought those cases that put the PSU at the front of the case were a good idea (see Lian-Li PC-A05)... WTF happened?!?! I can only get that if I buy an overpriced Jonsbo?

Is the Inwin 303/301 my only real option here for a new case? Looking for suggestions, please... cases with the PSU up top or at the front please.
 

Kardonxt

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Make sure you leak test your loop and you won't have any problems. If you are afraid of "big zappy zaps" then water might not be right for you.

Most cases have the psu fan side down so it sucks in fresh air from under the case. Any water should just puddle on the solid side of the PSU. I wouldn't expect any zappy unless you have a major leak which would probably damage other components anyways.
 

Nobu

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I don't recommend the 301 unless you're fine with one or no fans on the bottom, or don't plan to use the bottom two or three pcie slots on a uATX mb. If you're fine with that, plan on having bottom/rear intake and front exhaust, and only 120mm fans.

Otoh, if you're planning on modding the case, you can take out everything– the fan shroud, cable management, drive cage(s), and mb tray/psu shroud (one piece, unfortunately), more or less in that order.

Edit: Going to reiterate, because it can't be stressed enough. A uATX mb extends all the way to the bottom of the 301. Any fan will cover headers on the bottom edge, and an 25mm fan will cover the bottom pcie slot completely. Bottom fans may interfere with 2.5/2.75 slot GPU cooling shrouds.

Ed2: Said 303, meant 301. Fixed in post.
 
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cyclone3d

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I like the PSU at the bottom.

That being said... almost all cases available these days and in the past have some horrible design flaw that should have been caught by anybody at all that actually builds computers. It is as if the people who design cases have never even built their own computer.
 

mnewxcv

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Cases aren't designed to account for hardware failures. The bottom keeps them cool, giving them their own fresh air supply.
 

Nobu

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Actually, thinking about it, you could probably mount the PSU in the front of the 301 if it has a 120mm fan and is slim enough to clear the mb and ram. Just remove the fan shroud, pull the screws out of the fan on the PSU, and install on the fan shroud. Might void your warranty, and you'd want to flip the fan so it exhausts out the front...this is required, because front intake is terrible in the 301.

There are probably other cases where such a mod would be much better suited, if you were so inclined. If you do, plan to use a small ATX or sfx-l psu, because most larger ATX PSUs use 135mm fans or some other odd size...and they're big, besides.
 

GotNoRice

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I've noticed that most current mainstream cases seem to mount the PSU below the motherboard. I'm guessing that this is so the PSU doesn't have to suck in warmer air and the CPU can hang out in the warmer air instead?

If you have a significant difference between the air temperature at the top of your case and the air temperature at the bottom of your case, it's time to increase your overall airflow. If your water-cooling setup is leaking, especially to the point of actually dripping liquid, you have bigger issues than where your PSU is located. Most water-cooling leaks are pinhole leaks that don't actually drip, but instead just allows the liquid to gradually evaporate over time until cooling performance is compromised.
 

undertheradar

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@Nobu
I'd go with the 303 anyways; I was just acknowledging that the 301 is technically also an option.

@Kardonxt & @GotNoRice
I'm an EE who has water-cooled everything for over a decade & that's not a brag: what I'm getting at is that as an EE, I can't help but think "WTF?!?!, who designs a case for water cooling like that?" If I designed an industrial control cabinet with 480Vac routed through the bottom of a cabinet where water buildup is highly possible or underneath a condensing unit I'd be violating standards and asking to get in trouble. I've had a little drip here & there during assembly/disassembly, and I don't want water dripping down onto circuits that regulate power to the whole system. If I drip a little onto a graphics card or the mobo... its usually while the computer is off anyways, and if its not for some reason then distilled water really isn't all that conductive anyways when you're talking <12VDC. At most I cause a shutdown that I can still recover from or at the very worst I end up frying that component. If I drip water into a PSU I risk frying EVERYTHING. If there is water on the component, its usually pretty easy to see and wipe up. If I drip water into a PSU I can't just wipe if off with a cloth let alone see if everything is dry before I power up. Even when a PSU is switched "off", it still has 120 Vac going into it too so to be safe when working on a water cooled PC I have to unplug the power cord too just in case water drips in it?

All just so the PSU is in a cooler spot in the case drawing air from under? Yeah, because modern PSU's are sooo sensitive to heat, lol. If a case suffers from an actual thermocline that bad then it needs some flow. No reason a PSU at the front of a case or even at the top can't draw fresh air in from a side or top duct anyways.
 

RazorWind

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Most of the good cases these days enclose the power supply in a totally separate compartment. It's unlikely that coolant leaking from a liquid cooling system would make it past the shroud and the power supply housing.

You'd really need to be a lot more worried about a leak getting the coolant onto the motherboard or graphics card, both of which are usually more expensive and delicate components than the power supply, and don't usually have protection features built in.
 

criccio

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Not to mention, people have been building in and water cooling PCs for years with bottom mount PSUs, you just don't hear about issues with the power supply getting wet.

I think you'd have to make some kind of catastrophic building error for that to be a real concern. Most PSUs are raised up a few mil as well.

This just isn't a common concern and there is no consistent PSU failures because of it to warrant it being one.
 
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I guess I can understand OP´s concerns, when it comes to electricity, you can never be too careful. I guess most PSU nowadays have a top or bottom fan configuration, but I suppose you could look for one that has the fan on the side, like older models, that way if it ever drips a bit, it should hit the PSU lid and not cause "zappy zaps".
 

TordanGow

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I've noticed that most current mainstream cases seem to mount the PSU below the motherboard.....
......Having the PSU at the bottom of the case seems like a bad idea for anyone doing water cooling.....
....WTF happened?!?!
Wtf happened? Watercooling isn't mainstream. You might be surprised to hear this, but mainstream cases are designed for mainstream users.
 
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