Thoughts about air cooling

[Zubkover]

Hi,

after watching some media form Linus(Positive vs Negative air pressure and wife's rig mod) and other channels I felt kind of puzzled. Especially about the top fans as intake ones. 
Just think about it. It's like defying laws of forking physics. For what the hot air goes up, when the fans are set downwards?
It causes only "air disturbance", especially on low RPM fan settings, which leads to higher temperatures in the case.

Another thing that I was thinking about was usage of such limited space which is between a GPU and PSU. Since the PSU fan is facing the darn floor, there is a lack of air pressure, so the GPU can't take air in flawlessly.
So I took my 90mm addidional fan, wired it up, connected it to PSU through silver rods and cables inserted in molex connector. Then I screwed it to the top of the PSU, where are holes for those, who mount the PSU at the top, not the bottom, of the case.
This schematic actually looks kind of interesting, since I was able to achieve some temperature and air circulation improvements. My HD 7850 now tends to have up to 10o Celcius less, when on medium and heavy workload, when the fan is set around 800-900 RPM.

What do you think of it, lads?    

[LemonSpice]

Hi,

What do you think of it, lads?    

the size of the case maxes the hot air rises rule irrelevent the best config is the most fresh air on cpu and gpu

[Zubkover]

Still 1-3 fans at the front seems like a way better idea to do it...

[Rorgash]

considering the extremely fast speed of the air going into and then out of a case, heat never have time to go up, so instead with intake in the top and front you get the air to move even faster and out the back of your case, past the cpu and gpu. instead of turning the air up sideways and sorta making less air go past the gpu

[Aniallation]

the size of the case maxes the hot air rises rule irrelevent the best config is the most fresh air on cpu and gpu

It doesn't matter in a PC case with good airflow anyways, since hot air takes a lot longer to rise then the people who say it makes a big difference in a PC case thinks it does.

[LemonSpice]

It doesn't matter in a PC case with good airflow anyways, since hot air takes a lot longer to rise then the people who say it makes a big difference in a PC case thinks it does.

exactly what i meant

[AlwaysFSX]

Hot air rises slowly, if you've got more volume going in than physics would have going out, it works.

[Zubkover]

considering the extremely fast speed of the air 

What? D: I have one of the fans at 1200-1500 RPM... I don't feel literally ANY air pressure about 5-8cm away, so the speed is only at the very point of fan movement D:

[Rorgash]

i use noctua fans, so they move air a meter away at half that rpm

[Zubkover]

I sense some hellish technology D:

Since I'm in that country... Well... no Noctua for me I guess D:

[WoodenMarker]

Hot air rising doesn't make much of a difference in cases. It makes more of a difference in a room since colder air rests closer to the ground and you'd want the cold air at your intakes when possible. 

 

Another thing that I was thinking about was usage of such limited space which is between a GPU and PSU. Since the PSU fan is facing the darn floor, there is a lack of air pressure, so the GPU can't take air in flawlessly.
So I took my 90mm addidional fan, wired it up, connected it to PSU through silver rods and cables inserted in molex connector. Then I screwed it to the top of the PSU, where are holes for those, who mount the PSU at the top, not the bottom, of the case.
This schematic actually looks kind of interesting, since I was able to achieve some temperature and air circulation improvements. My HD 7850 now tends to have up to 10o Celcius less, when on medium and heavy workload, when the fan is set around 800-900 RPM.

Not sure what you mean. Pictures would help.

[LogicalDrm]

Fans pretty much cancel the physics inside the case since they are the force moving air. Since PSU fan is intaking one, using it as exhaust is only good idea when there is lot of space between it and GPU. In my opinion, this situation is also depending on intakes front, bottom and side. If you only have one small intake in front, using PSU as exhaust is not so good idea. GPU will basicly sufficate. But when there's more than one fan and room between PSU and GPU, you can easily have it as exhaust. Same with putting PSU on top position. Its used as exhaust since CPU is already cooled by stock/aftermarket cooler which pushes air away from it.

[Zubkover]

Lemme take some pics then WoodenMarker ^ ^

Here:


And since in my city there is no such thing as a molex female connector I used sth like this:

[Trik'Stari]

All of these things are why I have an air 540, and why I believe laminar flow to be better than positive or negative pressure. Equal number of fans intaking as there are exhausting. The only thing I've yet to do is block up the little vent holes beside the expansion slots, and above the rear exhaust fan, both of which cause a "leak" causing turbulence and disrupting laminar flow.

[DigitalHermit]

The action of hot air rising doesn't really matter much in a case...

 

You'd want to have a smooth flow of air through the case so, say you've got top, front, and bottom intakes, and rear and PSU exhaust (bottom mounted)... The pressure created by the amount of air going in vs going out would just overwhelm the effect of hot air rising...

[LogicalDrm]

Lemme take some pics then WoodenMarker ^ ^

 

 

You need to @ members to tag them into post. Besides that, your PSU is working oppiste than what pic shows. PSU fan is intaking one by default. Unless you deside to flip it which would be unwise since PSU will need more cool air than passive intake will provide.

[WoodenMarker]

Fans pretty much cancel the physics

Nice wording..

Lemme take some pics then WoodenMarker ^ ^

Ahh, looks alright--other than the cable management. I'd personally make the too fans intake to keep dust out unless you have a fan in the front 5.25" bays and the top fans are exhausting at low speeds like I do.

Interesting bit with the gif. How'd you do that?

[LogicalDrm]

Nice wording..

 

If that was @LinusTech quote, it would make great Tshirt.

[Zubkover]

@LoGiCalDrm Yea... true thing about PSU... I've just realized that. And Yes, the dust is on the dust filter just beneath the PSU, so it's intake.

@WoodenMarker Well... Cabel Managment you say? Just... 2 or 3 weeks ago EVERY cable was in that middle section stripped down with zipties, but I made PCI-e and mobo power connectors go behind, and SATA and Molex just doesn't have other way to lie themselves, not couting in the front panel I/O cabels, which are kind of too short to do anything beside what I've done to them.
And yes, top are 600-700RPM exhaust, while top is intake just at the bay.

And... I've made this GIF in Camtasia Studio 8... just becasue. I wanted to go in the quality, but I've failed with PSU, cat dang it.
Anyway, it took me 20-40x times more than just sending the pic on imgur or whatever, but it was fun to do it. : 3
If ya have a vid to be edited or know a way to open up new CS5's... Just drop me a PM, I'd be delighted to help and receive the solution to this sign up CS5 problem ^ ^

[Zubkover]

Ow, and I forgot about 1 little thing.

I did some work to prevent the dust from coming in the case, since it's "heavily perforated", and I couldn't find literally NO SOFT DAMN FOAM to make the dust filter... so I went with Linus suggestion which was in one of the Quickeys vids:

 

There were "Dogs in pantyhose"... I've created a start for a trend "PCs in nylon kneesocks"

And yes, it's taped there, since I couldn't stretch it properly. D:

Ow, and yes... it actually works well enough.
Approved.