PSU gets hotter after shutdown.

slyfox2151 said:

Hello,
watch this video (2:45 seconds into the video to be precise)
http://www.techpowerup.com/124012/T...hpower_Grand_80_PLUS_Gold_Certified_PSUs.html



according to there test, a random brand PSU without there delay cool "technology -.-" will incress from 50 C to nearly 70 C in tempreture when you turn it off, is this really correct?


after you shutdown the PC and the PSU turns off, why would the tempreture incress if the heat production has stoped? the air would get warmer yes but the componets them selves should get cooler not hotter.


is this a flaw in the way they messure the temp / gimmic?

Click to expand...

That graph shows a typical psu as being the red line when turned off the fan stops immediately and the components heat up initially, the one he is talking about is the blue line where the fan stays on longer so you dont have the jump in temps.

Thats what they say, though it only spun for 2-3 seconds after it was turned off from what I saw?

That TT would probably stay hotter than most longer due to the lame ass heatsinks it has inside it lol.

I would have to say it make little or no difference if the heatsink(s) can handle the heat and remove it.

it really doesnt matter. they're skewing the results.


All this means is that their PSU with the delay will cool down to ambient quicker... which doesnt really mean anything. the PSU was operating at those temps, so how is it going to harm it?

heat production simply doesnt continue with the system off, so the temps dont increase on the HARDWARE, but the *air* in the PSU case might - heat is still leaving the PSU components and travelling into the air, but not being pushed out of the enclosure. so the PSU itself is cooling down quite nicely, its the air that isnt.

If you dont get how that works, think of it this way: your bladder is full of hot, steaming urine. you take a piss. suddenly, the toilet waters temperature rose. OH NO. but you (the source of the heat) just dumped a ton of heat out of you... so you're cooler. its just the area around you that got warmed up.


dont forget that sudden changes in temp causes expansion/contraction, which is what slowly kills hardware by cracking solder joins and so on. IMO its best to let it slowly cool down over a minute or two, than their method.

In my opinion that fan delay thing is just a gimmick, some marketing thingy.

Mussels said:

it really doesnt matter. they're skewing the results.


All this means is that their PSU with the delay will cool down to ambient quicker... which doesnt really mean anything. the PSU was operating at those temps, so how is it going to harm it?

heat production simply doesnt continue with the system off, so the temps dont increase on the HARDWARE, but the *air* in the PSU case might - heat is still leaving the PSU components and travelling into the air, but not being pushed out of the enclosure. so the PSU itself is cooling down quite nicely, its the air that isnt.

If you dont get how that works, think of it this way: your bladder is full of hot, steaming urine. you take a piss. suddenly, the toilet waters temperature rose. OH NO. but you (the source of the heat) just dumped a ton of heat out of you... so you're cooler. its just the area around you that got warmed up.


dont forget that sudden changes in temp causes expansion/contraction, which is what slowly kills hardware by cracking solder joins and so on. IMO its best to let it slowly cool down over a minute or two, than their method.

Click to expand...

+2

Did not think of that till you said it.. Dry joints is a killer.

My Hiper TypeR 580 has a tiny 70mm fan on it that stays going for ~2mins it doesn't move a shit load of air but just enough so that some cooler air is being dragged into the PSU for the last 12mnths no problems here with cracked solder joints as yet and it usually runs around the 60~70% mark all the time so fairly warm although now I have my RV02 case and it sucks cool air in from outside the case i have noticed a considerable temp drop off

i remember some time ago a psu that reportedly exhausted the hot air for a while after you switched the pc off, i think it was a hyper or something of a similar name, haven't heard of it since though
i have the side of my case off anways so it would be a pretty useless gimick tbh
as for psu's heating up, well i think that's inevitable (i usually switch mine off at the wall) so

well most expensive psus do that, even this cheiftec one does