Need airflow help

[naadra]

Hello everyone, I am about to install my other 6950 in my 690 II Advance case. Before I do so, I would like to finish setting up the rest of my fans at the same time so I do not have to go back to move wires etc again. So I am trying to figure out the best fan config for my setup. Now for reference the 6950s I am using are http://www.newegg.com/Product/Produc...82E16814127555. They are rather large and basically the top card effectively cuts my case in half, with just one inch between the card and the cage slot where my HDD is. Now I know these cards produce more heat then most, so I am trying to configure the best set up. So here we go! Hopefully this picture works!



The green is just my power supply, cpu cooler, and hard drive. The red of course is the video cards, and the yellow is the fans. I have removed the bottom hard drive cage already. For the top I was going to put a fan in the unused 5.25 bays blowing cool air directly on to the push/pull on my 212, with two exhaust fans behind the 212. One on top and behind the 212 and of course one in the normal rear of the case behind the 212. I will most likely be placing a slim 80mm on the right side panel as well for sucking heat from under the motherboard. For the bottom/front I wanted to go with a real high 140mm/cfm/rpm ( or some thing that will move a lot of air fast towards the cards ), and for the side of the case (the lower fan slot ) another good fan blowing directly onto the cards. The cards themselves blow air out of the case from their ends. I was also going to remove all the unused PCI slot fins from the back of the case to have more of an exhaust type outlet for the bottom area/back of the case. As you can see the case airflow wise, is essentially two separate chambers it seems. My main concern with my fan set up at the moment is mainly the GPUs, especially the top card. I was even thinking of installing the top 5.25 fan at an angle blowing directly down onto the top card as well, kinda half of the airflow on the card and the other half going into the 212. I know my CPU area will be fine to the best of my knowledge. If anyone could give me some better fan set ups, or ideas/suggestions it would be much appreciated. This is the best that I could come up with so far and I am about to go nuts thinking about it lol.

Thanks

System
Windows 7 SP1
CM 690 II Advanced
Corsair TX850 V2 Enthusiast Series
I5 2500K / No OC ATM
Gigabyte GA-Z68X-UD3P-B3
G-Skill (2x4GB) 8GB 1.25V DDR3 1600 Sniper Series
2xMSI HD 6950 2GB / No OC ATM
Samsung Spinpoint F3 1TB 7200 RPM
Sony Optiarc CD/DVD

[Djinni]

Great job with the picture :-)

I really wouldn't remove the PCI expansion slot covers unless the slot is in use, It may seem like a good idea, but in practice it actually disruptes the airflow of the case design and increases the dust buildup inside the machine.
I would have the Top, Front and Bottom on Intake, and the rest on Extract, the side ones are debateable...

If you want to optimise this, it will also depend on where your machine is in the room, and what airflow there is outside the case too... (no point blowing hot air from your room into the case, and cool air from your case into the room.)

Alot of people seem to put their machines near radiators or windows. or even both! (like me lol :P) So having the fans near the radiator on intake is counter productive.

[naadra]

Ya my case sits flat on a raised table and its normally about 68 to 70 degrees in my room all the time (hug AC unit). It is just near a wall with no other heat sources near it. but has plenty of space around it for cool air to come in from any area ( Ac vent is directly above the unit as well). The main reason I wanted to remove the extra pci slot fins was so the air in the bottom had some where to exit besides just the few inches of space it has to get to the top. From the bottom area of the case the only place for air to really get to the top area of the case is just the one inch space in between the HD and the GPU, and from the side of the case the top of the gpu is only like 2 inches from the side panel itself. I think the bottom GPU will be fine temperature wise, its the almost less then one inch in between the top and bottom cards I am really worried about. I think the top card is going to get super hot.

I understand what you mean about the design of the case and disrupting the airflow in regards to the PCI slots. I almost want to just go with every fan I can in the case (minus top left side fan), but could not find any Coolermaster articles with what they intended the airflow setup to be ( Been researching this for like a week lol ). IE should it be exhaust wise / both top and rear fans / with intake both bottom front and side fans /. I would think with five intake and three exhaust that would create a nice positive pressure in the case. I am just really undecided on what set up to go with. I have read so many articles on it and I keep getting conflicting information.

Thank you for you input Djinni!

Anyone else have any suggestions as well?

[Djinni]

Lots of people do it differently, But typically the best setup is to blast cool air from outside into the case, and expell hot air out of the case. So you want the air from the AC unit going into the case with the air in the case going to the opposite side the room. So from what you said, i'd reverse what I said....
Do Top, Back on Intake, and Front and side on Extract. Bottom i'd probably have on intake too really.

[naadra]

Thanks for responding again Djinni! The air in the room is all basically the same temp regardless of what side it coming from for the most part. It is not like a forceful stream of air coming down from the ceiling or anything like that ( I wish it was though! I would scooch my bed over here lol ). I think I may try a couple different ways with a few extra fans I have laying around.

One other question, is there any major disadvantage having my HD in a 5.25 bay? I have the brackets etc for it already that came with the case. Was thinking I can just mod the case by removing the hd cage altogether and that would solve all my problems. I would be able to stick fans aiming right down in between the cards from the front and have improved airflow to the top of the case again. This is mainly a gaming computer only with surfing of course, I have another computer that I use for all my other stuff. So would there be any major issues placing the hd in the 5.25? The only programs that will ever be running on this computer would be games and computer monitoring stuff ( cpu-z etc ).

Thanks again !!

[Djinni]

No, there is no problem with putting your HDD in a 5.25" bay. if you have a bracket all the better, but your HDD will happily run on the floor of your case. Just remember not to move the case with the drives loose.
Obviously the more secure you can make the drives the better, (IE the less vibration they get the longer they last and the better they perform.)

But we often put 2.5" drives in a 3.5" drive bay. Just look at the SSD's we use now.

[Riff]

The general idea is:

Front/Side - In
Rear/Top - Out

That's the simple version, then you can switch a couple around, or have them all IN/OUT - check if it makes it hotter/colder,

[Adappy]

Personally I'd put the card in first and see how your temperatures are. I have the same case and I have experimented with adding more fans/moving them around and I never saw any drop in temperatures that weren't within the margin of error/ambient temp changes, both when I was originally running SLI GTX 460's and when I got my GTX 580, all adding fans did for me was make more noise.

If anything would help, the top card should be hotter than the bottom card, and the trick would be getting air between the cards... which would be somewhat difficult with the way the top HDD cage is pointing. Not mounting a HDD in the top part of the cage would probably the only thing you could do to feed it more air from the front 140mm fan (which I'd recommend mounting in the upper position). That or a fan on the bottom part of the side panel.