Bottom PSU cases
- Thread starter ticktock
- Start date
Generally the cases with PSU's at the bottom have them in a seperate compartment, which makes rising heat less of an issue. As for wether it makes a real difference... i wouldnt have thought so. The PSU at the top of the case will suck warmer air in the bottom from the CPU/RAM and expel it straight out the back so it's less likely to be swelling around in the case.
I think the location in those tests is coincidence, rather than fact.
I think the location in those tests is coincidence, rather than fact.
i prefer bottom!
cooler running PSU
cpu ram sit next to a 140mm and 120 mm fans
hot air sucked off my x-mystique
the only issue i have had is the p4 power connector
and i wish the mobo mfgr's would mount the atx power and p4 at the bottom of the mobo
that would make me vrrrry happy
cooler running PSU
cpu ram sit next to a 140mm and 120 mm fans
hot air sucked off my x-mystique
the only issue i have had is the p4 power connector
and i wish the mobo mfgr's would mount the atx power and p4 at the bottom of the mobo
that would make me vrrrry happy
how can the heat rise from the PSU if there is a (in most cases) 120mm fan sucking air down and out?
PSU's position on top of the case as exhaust was designed at time when CPU's had "huge" maybe even ~5x5x2cm heatsinks without any fan and graphic cards hadn't really even heard about heatsink.
So just because it happened to be many years in there doesn't make it valid reason for keeping it in there anymore.
So just because it happened to be many years in there doesn't make it valid reason for keeping it in there anymore.
That's something done more efficienctly by plain fan.
Sounds like the general thoughts are that it's an ok system as long as it's partitioned off?
I have the P182, which is partitioned, and the temperatures are very good compared to my previous top mounted case, but that is for a number of reasons. I do believe that bottom is better though, seems to make sense now, with so many hot components in/near the mobo.
I have the P182, which is partitioned, and the temperatures are very good compared to my previous top mounted case, but that is for a number of reasons. I do believe that bottom is better though, seems to make sense now, with so many hot components in/near the mobo.
If i had the choice i'd prefer to have one of the largest cables going into the pc at the bottom near the floor rather than trailing up and getting in the way just because the pc world has kept an unusual trend going.
As for heat, i can only assume having the PSU at the bottom would allow for cool air to run over the components, aiding to keep it stable. Rather than having warm air from the rest of the case rising into it... though how much difference this would really make i don't know.
in an ideal world i'd like my Power cables at the bottom, VGA at the top (screens don't sit on the floor with the case now do they?) and graphics cards would have the coolers and main circuitry on the top so i could see it better through my side panel
As for heat, i can only assume having the PSU at the bottom would allow for cool air to run over the components, aiding to keep it stable. Rather than having warm air from the rest of the case rising into it... though how much difference this would really make i don't know.
in an ideal world i'd like my Power cables at the bottom, VGA at the top (screens don't sit on the floor with the case now do they?) and graphics cards would have the coolers and main circuitry on the top so i could see it better through my side panel
Moving air from one place to another isn't conducive to removing all heat from the same place. It works as a reduction, but heat will still rise. It takes more than a fan to counter convection.
Pointing the fan on a PSU up or down wont make a difference, as long as there's a gap below the PSU.
I mentioned it as a by-product of being at the top of the case, not as a reason to do so.
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ok so if you had space you could turn your PSU over and it would not make a difference yeah right. haha
i currently have a 3GHz P4 running at 3.86GHz
ram also 15%
9800GT overclocked to 700/1000/1600
Temperatures
Motherboard 29 °C (84 °F)
CPU 34 °C (93 °F)
GPU 38 °C (100 °F)
GPU Memory 30 °C (86 °F)
GPU Ambient 27 °C (81 °F)
Maxtor 6L200P0 25 °C (77 °F)
SAMSUNG SV0813H 21 °C (70 °F)
SAMSUNG SV0813H 22 °C (71 °F)
amb room temp 20 °C
all stock cooling
thanks you bottom mounted PSU (You Rock!!)
If you have a 1 cm gap below a bottom mounted PSU and the fan is underneath, the air will be pulled into the gap from the surrounding area just the same is it would be pulled into the top if it were facing the other way up. I'm not sure how you can begin to argue that, because it's just a fact. When the air is removed from the space below the PSU, it is replaced by more air, that is moved from somwhere else in the case.
The reality is that the difference in temperature this would cause in a case is very little.
The reality is that the difference in temperature this would cause in a case is very little.
Clearly our CAD abilities are beyond mere words. There's nothing in your picture i'm not already well aware of. You understand of course, you could flip that PSU over and have the same effect right? 
The air would still be drawn downwards, because it would move there to replace the air that the PSU would be removing.
Also, you'll note in my original example at the top, that i mentioned bottom PSU's often being partitioned in seperate compartments, for example in the P180 series; in which case this whole discussion of paint-based retorts is moot
The air would still be drawn downwards, because it would move there to replace the air that the PSU would be removing.Also, you'll note in my original example at the top, that i mentioned bottom PSU's often being partitioned in seperate compartments, for example in the P180 series; in which case this whole discussion of paint-based retorts is moot
Clearly our CAD abilities are beyond mere words. There's nothing in your picture i'm not already well aware of. You understand of course, you could flip that PSU over and have the same effect right?
Also, you'll note in my original example at the top, that i mentioned bottom PSU's often being partitioned in seperate compartments, for example in the P180 series; in which case this whole discussion of paint-based retorts is moot
hay was this not a discussion about top v bottom
think we have killed this one
i dont think it dose really make a difference if its upside down or not or partitioned
but i do think bottom mounted PSU's win
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PSU doesn't heat anything above it because air drawn into PSU (where it absorpts heat) by its fan can't go to anywhere else than out from PSU through its rear removing that heat from case.
(and because there's only heat of PSU's losses to be removed fan speed/airflow doesn't need to be high for keeping PSU's components cool)
Only situation when temperature difference based air movement becomes actually significant in PC is when it doesn't have active cooling. (fans)
Best example of convection are cumulus clouds which form when sun heats air near surface and it rises upwards to lifting condensation level where water vapour starts to condense.
I'm sure you've seen many times (or has Homo Sapiens Urbanus gotten that far from real world?) how those clouds starts to rise nicely and you think there's going to be thunderstorm only to see those clouds turn to pancakes ten-fifteen minutes later.
That happens because there's layer of "warmer" air (actually it's only lack of temperature dropping fast enough with altitude) and rising air just doesn't have enough momentum to push through.
(you have lot of capping inversion there in UK)
Reason for compartments in P180 is keeping airflow as controlled as possible for minimizing number of needed fans and noise.Also, you'll note in my original example at the top, that i mentioned bottom PSU's often being partitioned in seperate compartments, for example in the P180 series; in which case this whole discussion of paint-based retorts is moot
With perfect airflow control PC would need only either exhaust or intake fans because air couldn't come from/go to any other place than needed naturally cooling all components on its way through case.
Most efficient (best cooling with least amount of fans) airflow for PC case is front in - back out, holes/fans in everywhere else just messes this by either creating short circuit or drawing air out prematurely leading to lesser airflow for components needing that airflow.
One top exhaust immediately and only directly above CPU can help in maintaining this airflow but anything else won't: One user had 10C CPU temperature drop after making airflow guide which guided intook air toward CPU instead of being drawn out by top exhausts.
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Obnoxious, irrelevent and completely missing the point. Using latin words doesn't make you clever. Nor does it change the fact that 1 120mm fan is not sufficient enough to completely remove all heat from an area of air. The 120mm does not fill the dimensions of the area of the case that immediatley surrounds it, thus there will always be areas that are not directly affected by it. Heat will still rise, albit hugely reduced. Take a PSU, put it in a small box, fan up, then put your hand over it. It will still be giving off a small amount of heat.
This is the only point im making. I care nothing for nephology. Especially Cumulo Nimbus, Cirrus or any other stored form of potential precipitation
But what would a mere urbanised human know of such matters?Really?
Please quote the part where i disputed that.
Ok?
Doesn't change the fact that turning a PSU upside down in the bottom of a case would hardly affect the surrounding temperature. And honestly, since we are being honest here, i have no idea why you've quoted me to write that, because it's got nothing to do with anything i've posted so far.
Edit: Actually, don't quote anything, and don't reply. i shant read it. I obviously cannot type in a sense that you will understand the point i'm trying to make, so i wont type any more points.
Turn your PSU any way you like, inside our out of your compartments, because i really wasnt telling anyone do do anything differently. Watch out for clouds though