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Negative Pressure - no intake fans

Kammster

New Member
Joined
Nov 26, 2006
Messages
188 (0.03/day)
Location
Guyana, South America
Processor Sempron 64 2800+ DH-E6 (@2Ghz - bios limit)
Motherboard DFI NF3 250-AL (@250 FSB - 2000 HTT)
Cooling 92mm + 80mm Exhausts / Amd HSF mod:80mm fan + VF700 cuLED [mod to x800 fan control]
Memory 1GB Buffalo DDR 400 @416 3-4-4-8 1T
Video Card(s) Sapphire X800 GTO (broken- sapphire is BAD)--256mb 6200
Storage WD 120 GB Caviar SE + 1GB Flash [80GB 7200.9 offline]
Display(s) 19" Samsung Widesceen LCD
Case Xtech cheapo
Audio Device(s) onboard - Realtek 6Ch
Power Supply Coolermaster eXtreme Power 550W w/ Antec 120mmLED
Software Windows XP SP2 + nforce 76.45 + nforce 5.10
How it works:
CPU : intake funnel + amd fan + 80mm exhaust (restricted vent holes) (31 deg idle)
Gfx : side panel intake vents + zalman + 60mm exhaust (39 deg idle)
PSu exhasut + intake vents in front of hardrive (32 deg idle)
chiptset 34deg (idle)



I just wanted to exhuast the hot air from the case before it statred to effect the generic psu, so i cut a hole in the thin sheet metal, and installed a 60mm fan for testing and i got a big surprise!
not only did hot air vent out faster but the other components got as much as 5 deg cooler.

before chipset hit: 43 deg under gfx card heat
after : 38 deg / 39 deg(silent)

the temp drop was also on the cpu load temp 42 to 39
but the gfx card was best; before my max temp never varied with clock frequency always 63 deg.
now 300:350 (barely 54 deg); 415:496 (59/60 deg)


my theory is: basic fliud mechanics volume in = volume out. the exhaust fans pull so much air out of the case that they not only pull in air thru the vents but also cause air in the case (hot air) to move in currents to the exhausts(2+psu).


i am 60mm(25mm thick) 12v@0.12V thta i got from a car parts store.
also tried a spare fan from a mircofin socket A cooler:
dynatron mircofin (15mm thick) 12v@0.25v top speed 5200 rpm (loud -48 db), i forgot the temps because it was too loud, @silent(5v) was same.
 

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quick update

there is dust everywhere, any place than air can move there is dust, behind the hard drive the front grill thing has dust spikes like a fan blow it there.

had to take out the 80mm fan for another case, put in a 92mm and it really kicks
temps gpu @ 400:425 57core:45mem
and the temp falls fast when the load stops.

vibration from the fan on side panel was bad but got a idea from a generator room and used rubber strips for patching bicycles to dampen the noise.
 

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actually positive pressure is more desired than negative ...
 
actually positive pressure is more desired than negative ...

really? so air just starts flowing out type stuff?

EDIT: I always though balanced pressure was the best?
 
really? so air just starts flowing out type stuff?

EDIT: I always though balanced pressure was the best?

I got intake front, exhaust rear... That's the best setup i've tryed so far and works preety well.

Let´s see if i find some pic with my temps before my mobo dies...
 
Found it, Everest Temps right there, and Shitty BG with my name xD
benchsoq1657.jpg


Black = HD
Blue = GPU
Brown = CPU
Green = Mobo

And those aren't my best temps :P coz that ones was after running the bench xD
Best Idle were 25 HD, 20 GPU, 26 CPU and 19 Mobo...
Believe it or not :D

See'yas!
 
Found it, Everest Temps right there, and Shitty BG with my name xD
benchsoq1657.jpg


Black = HD
Blue = GPU
Brown = CPU
Green = Mobo

And those aren't my best temps :P coz that ones was after running the bench xD
Best Idle were 25 HD, 20 GPU, 26 CPU and 19 Mobo...
Believe it or not :D

See'yas!

i believe you. my friend is running his e6600 with stock cooling and thermal paste, and it idles around 28 when it was ~65 F. he has one intake on the front, one intake (cpu sleeve thing) one side, one exhust on side, one exhust on back, and the psu. very cool system, you can feel the room heat up (i guess that's not a good thing, lol) sounds kinda like a turbine when it's running though....in a good sort of way.
 
actually positive pressure is more desired than negative ...

From my experience and a few of my IT buddies, they find a close match to a 1:1 ratio serves well, you have your exhausts up high and rear, intakes low and front, it helps replenish the exuasted hot air faster with cooler air than negative, since you have fans pumping air in. Posotive I believe would be more intake than exhaust, which is the least effecient method, it will not be able to remove the heat as quickly, which is the goal with OC'd PCs. If you have more air moving in the case, but not exhuasting hot air efficiently, you're trying to cool your components with hot air, doesn't make much sense, but posotive is supposedly the best way to keep dust to a minimum. I'd rather clean my PC more often and get more effective cooling. I may be backwards on those, but that's how I understood it.

Also, IRA, you gonna fill out your system specs in your User CP so we can see whatcha got running? I'm kind of curious, because it seems like you have some OC experience. Let's see what you have.
 
pc is currently down .. waiting on a vid card .. got a E6400 ... 2 gigs o ram, ABit AB9Pro, stock intel cooler for now
 
Nice, keep us posted on how it turns out!
 
i believe you. my friend is running his e6600 with stock cooling and thermal paste, and it idles around 28 when it was ~65 F. he has one intake on the front, one intake (cpu sleeve thing) one side, one exhust on side, one exhust on back, and the psu. very cool system, you can feel the room heat up (i guess that's not a good thing, lol) sounds kinda like a turbine when it's running though....in a good sort of way.

Hahaha, mine is not sooo noisy, tested just all the fans, with the case empty (:cry: there is nothing in there) at 5 am, when the house is ultra silent and the only fan that made a noise, was lubricated and now is not noisy xD Ultra Silent Zera Cooling lol \o/
 
Hahaha, mine is not sooo noisy, tested just all the fans, with the case empty (:cry: there is nothing in there) at 5 am, when the house is ultra silent and the only fan that made a noise, was lubricated and now is not noisy xD Ultra Silent Zera Cooling lol \o/

lucky you, his sounds like a turbine when he starts it up pheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeewwwwwww but it does a good job at keeping it cool. and if he bought a fan controler, im sure he could leave them all at low and still get really good idle temps.
 
lucky you, his sounds like a turbine when he starts it up pheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeewwwwwww but it does a good job at keeping it cool. and if he bought a fan controler, im sure he could leave them all at low and still get really good idle temps.

Hahahaha, he need limits on those rotations xD hahaha the "phewww" thing was really funny hahaha
 
Hahahaha, he need limits on those rotations xD hahaha the "phewww" thing was really funny hahaha

lol thank you. he sort of does....i mean he's usally blasting music, or playing his guitar really loud....so the pheww isn't noticable. actually now that i try and remember, once it's running, you don't really notice it, it's just when you start it and it goes phewww, here's the case
 
lol thank you. he sort of does....i mean he's usally blasting music, or playing his guitar really loud....so the pheww isn't noticable. actually now that i try and remember, once it's running, you don't really notice it, it's just when you start it and it goes phewww, here's the case


Looks really sexy, mine is self-made hehe i cutted, drilled and tweaked myself... I'll upload some pics :D

And for the noise thing, my Heatsink used to do tons of noise too lol it wasn't "phewww" it was like "hhhhhhhhhhhhheeeeeeeeee" and was really annoying coz I couldn't hear at low volume xD and when the night is silent, arround 3~5 hs am, it was really unbearable... So I've reduced the RPM's of it and it worked still at good temps and ofc with much less noise... :D
(Taken with a webcam, my digicam is broken)
Before painting and mounting of the side Metacrylate (dun remember if it is spelled right) panel
ll.jpg


After painting and mounting of the side Metacrylate pannel and before the lights and side 120 mm x 120 mm fans \o/
Front
Nueva 3.jpg


Rear
Nueva 4.jpg


Metacrylate side
Nueva 2.jpg


And the other side (nothing special on it at the pic, made an AMD logo with vinyl on it)
Nueva 1.jpg


When I got my digicam working I'll post it on rate my case, now it's finished xD
 
Looks really sexy, mine is self-made hehe i cutted, drilled and tweaked myself... I'll upload some pics :D

And for the noise thing, my Heatsink used to do tons of noise too lol it wasn't "phewww" it was like "hhhhhhhhhhhhheeeeeeeeee" and was really annoying coz I couldn't hear at low volume xD and when the night is silent, arround 3~5 hs am, it was really unbearable... So I've reduced the RPM's of it and it worked still at good temps and ofc with much less noise... :D
(Taken with a webcam, my digicam is broken)
Before painting and mounting of the side Metacrylate (dun remember if it is spelled right) panel
ll.jpg


After painting and mounting of the side Metacrylate pannel and before the lights and side 120 mm x 120 mm fans \o/
Front
Nueva 3.jpg


Rear
Nueva 4.jpg


Metacrylate side
Nueva 2.jpg


And the other side (nothing special on it at the pic, made an AMD logo with vinyl on it)
Nueva 1.jpg


When I got my digicam working I'll post it on rate my case, now it's finished xD

yeah, it's sexy, just no side panel, and i don't think he wants to mod it (he's not even overclocking :wtf:). you have no idea how many cases we had to go through....it'd be like ....too blue....not blue enough....not enough fans.....to white (some weird stuff) but now....sexiness. wow, nice case. id defiantly give you a good rating (as long as you have good cable mangment, etc, the case is nice though)
 
yeah, it's sexy, just no side panel, and i don't think he wants to mod it (he's not even overclocking :wtf:). you have no idea how many cases we had to go through....it'd be like ....too blue....not blue enough....not enough fans.....to white (some weird stuff) but now....sexiness. wow, nice case. id defiantly give you a good rating (as long as you have good cable mangment, etc, the case is nice though)

Pics are way crappy, the cables were tied and moved away to let space for airflow, but now (before I taked all off) they were covered with a green (dunno how to say it lol) hmm thing xD and some green lights... It was nice... :D
 
Pics are way crappy, the cables were tied and moved away to let space for airflow, but now (before I taked all off) they were covered with a green (dunno how to say it lol) hmm thing xD and some green lights... It was nice... :D

green!!! :D a much different color than the normal blue.....i think i like green.....hmmm...actually, i think i like no lights and a slient computer so i can sleep with it on, of course since slient is not possible....LIGHT IT UP!
 
green!!! :D a much different color than the normal blue.....i think i like green.....hmmm...actually, i think i like no lights and a slient computer so i can sleep with it on, of course since slient is not possible....LIGHT IT UP!

It was everything black (Mate? it's ok?) but painted the inside of fluo green, and with the lights it rox ^^
Personally, I love black mate and fluo green \o/
 
It was everything black (Mate? it's ok?) but painted the inside of fluo green, and with the lights it rox ^^
Personally, I love black mate and fluo green \o/

lol i meant lights when i said green. just cause...well....idk maybe it's because our grass is dying. i think it'd be intresting to see something with a UV light, are there any case mods here that have a UV lighting?
 
lol i meant lights when i said green. just cause...well....idk maybe it's because our grass is dying. i think it'd be intresting to see something with a UV light, are there any case mods here that have a UV lighting?

I could change the green lights by UV lights... If you rate me 10/10!! haha
Already though it but preffered green ones, I can give a try :D
 
really? so air just starts flowing out type stuff?

EDIT: I always though balanced pressure was the best?


from the Ideal Gas Law , pV=nRT. Rearranging we get n=(pV)/(RT), so increasing the pressure increases the number of air molecules to conduct away heat.

im just theorizing still ...

Bless
 
I tested the positive air induction method, my temps increased by quite a few degrees C. The Ideal Gas Law makes sense, but at least in my application using More CFM Out than In (not by too much, based on est. fan airflow from specs) was the coolest airflow based solution. But if a few people try removing their case exhaust fan and only using PSU fan for exhaust, leaving intake installed and running, compare to current temps. That's the best way to verify is to try it out and see results with your own eyes.

IRA, you have any goals set for OC-ing that 6400?
 
yeah, i dont want to burn it up, lol. i live ina tropical country so 2.8 - 3.0 will do ... or 3.2 when im going to go crazy. i got a freezer 7 on the way still
 
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