Routing the air from fan right to CPU

[Garfield]

I saw an article on this that this guy just routed a case fan right to the CPU. Would this be hard to do? How much better cooling would I get? Would I use the duct to get it to an exaust fan because logically wouldn't the fan blow off of the CPU and then the duct would bring it directly out?

 

[funnyperson1]

no the best way i would think to do this is to have a big case fan on the outside and duct the air from outside your case onto the heatsink, your temps should lower by like 5-6degrees C depending on how good your case cooling is now....

 

[Yodums]

no the best way i would think to do this is to have a big case fan on the outside and duct the air from outside your case onto the heatsink, your temps should lower by like 5-6degrees C depending on how good your case cooling is now....

Mines like that. I have a small table fan, which I zip tied, horizontally right above the fan of my heatsink, that lowered it by 4 degrees... Then I added a bigger table fan behind it, blowing on all my mainboard and stuff, which lowered another 3 degrees..

It can be done easily, find zip ties and zip tie each side of the case fan to the case above the CPU Fan..

 

[Garfield]

How would I make this direct duct? Just cardboard? How would I fasten the two ends?

 

[Yodums]

Get cardboard, get a roll of duct tape. And use the cardboard to make a duct from the fan to the HSF...

Note: Make sure the system is off when your touching the HSF with some stuff, try not to even touch it. It's going to like move the thermal compound around and no contact is goign to be made.

Yodums

 

[nihili]

I saw an article on this that this guy just routed a case fan right to the CPU. Would this be hard to do? How much better cooling would I get? Would I use the duct to get it to an exaust fan because logically wouldn't the fan blow off of the CPU and then the duct would bring it directly out?

I'm assuming you're talking about routing air to the Heatsink, and not to the CPU itself. Routing air directly to the CPU will likely result in a fried chip. Direct die cooling won't work with air.

Ducts can be either exhaust or intake. Which one works best is going to depend on your sysytem. I generally have the best luck with exhaust ducts, but others have better luck with intake. The better the airflow through your case, the less difference there will be between the two. So set up your duct, and then try it both directions.

Ducts create some resistance to airflow. Ideally you want a large, straight, smooth duct. However, the easiest duct is to use dryer hose to connect your heatsink to the rear fan on your case. You can overcome the resistance by using a pair of matched fans, one on the sink, one on the case. Pay attention though, occassionally the fans end up interefering with each other rather than helping.

How much a duct will help depends upon the details of your system. I would expect a difference of somewhere around 3-8 C.

nihili

 

[Garfield]

Do any of you fellas have any links on how to do this duct? I thought I had found one on the main page, but I can't find it anymore.

 

[Ugmore Baggage]

The easiest and probably most effective method to do what you want is a blowhole.

You cut a hole n the side of your case, right across from the heatisink
Stick a fan on it,
then (optional) attach a tube to extend it to your Heatsink
I recommend adding a filter.

The easiest filter I've thought of consists of a furnace filter (smallest available is 10x20 inches) mounted about 1/2"away from your case door -- on the outside. Attach a frame around it to make it airtight. The huge surface area of such a filter should allow you to skip the horrible ones (that you can see through $.50) and get a good pleated model that should keep your innards spotless ($5). Add a grill if you must.

If there's one thing I hate it's cleaning, but I especially hate paying $5 for a can of freakin air!

An added benefit is you won't have to be particularly neat when cutting your fan hole because it won't be seen except when changing the filter. In my case, the rest of my holes will soon either have exhaust fans or small "vent" filters. All these filters are found at Home Depot or any hardware store.

 

[Garfield]

I don't think I'm going to go with the filter. I'm going to use compressed air for the dust problem. I don't mind that. But, your idea of cutting a hole directly to the heatsink is good. I'm not sure if I want to do that though. I want to do some modding in the future and that might be a hindrance. I think I'm just going to do the duct directly to an already existing case fan. Any links on how to do this?

 

[res0r9lm]

I don't think I'm going to go with the filter. I'm going to use compressed air for the dust problem. I don't mind that. But, your idea of cutting a hole directly to the heatsink is good. I'm not sure if I want to do that though. I want to do some modding in the future and that might be a hindrance. I think I'm just going to do the duct directly to an already existing case fan. Any links on how to do this?

you need a much bigger fan than the ones in you case. I'm using a 120mm fan at one end and a 80mm delta at the other and no fan on my heatsink at all. make sure that the fan is inserted into duct far enough to give you 1"-2" of clearance from heatsink that way you get better airflow to the center. with a normal hsf setup the fan motor gets in the way and causes a dead spot in the center. you should be able to get lower temps then me since your chip is putting out a lot less heat. also try to keep duct as striaght as possible. if your not sure about wish mods your going to do to the case keep side off until you decide what your going to do. one more thing don't shove duct over heatsink too far.this is not my idle temps they are full load folding for 2 hours if anything they will lower because of disturbing hsf seat when putting on duct

 

[Garfield]

I attached an image of what I think you explained your design to be, res0r9lm. So you took off the heatsink fan? A couple of more questions...

What is the duct itself made of?
What tools are needed for this?
How much would this cost?

I think this is what I'm going to do. I'm going to have to sacrafice some modding for better cooling. I'm willing to do it. Here's the image and tell me if I have it right. Thanks...

Garfield

 

[Yodums]

I attached an image of what I think you explained your design to be, res0r9lm. So you took off the heatsink fan? A couple of more questions...

What is the duct itself made of?
What tools are needed for this?
How much would this cost?

I think this is what I'm going to do. I'm going to have to sacrafice some modding for better cooling. I'm willing to do it. Here's the image and tell me if I have it right. Thanks...

Garfield

You need your 120mm to be where the big duct begins. Or else if it's too close, the air will just start fighting causing loss of performance, and the tube would be too big and it wouldn't be able to attach to anything.

 

[Yodums]

Something like this is better.

Keep in mind the 120mm intake leading to the duct to the HSF has to push alot of air.

 

[Garfield]

You need your 120mm to be where the big duct begins. Or else if it's too close, the air will just start fighting causing loss of performance, and the tube would be too big and it wouldn't be able to attach to anything.

I'm not quite sure I totally understand what you mean. Isn't that what I made my diagram look like? I put the 120 where the big duct began. Do you mean too close to the heatsink fan? That would be the problem?

 

[Yodums]

Oh sorry, I got confused with all the arrows. Yea it looks good. If you wish you can go abit extreme and buy a ducting product that mounts on the side of your case, looks very clean and neat, a good case mod.

 

[res0r9lm]

I attached an image of what I think you explained your design to be, res0r9lm. So you took off the heatsink fan? A couple of more questions...

What is the duct itself made of?
What tools are needed for this?
How much would this cost?

I think this is what I'm going to do. I'm going to have to sacrafice some modding for better cooling. I'm willing to do it. Here's the image and tell me if I have it right. Thanks...

Garfield

yea it looks simialar but is square. It's made out of a fed ex shipping box. didn't cost me anything I had everything just laying around. what you need is a cardboard box, roll of duct tape, and the fans $30 should be plenty. one thing put the 80mm fan closer to heatsink say 1" from it. use tape to narrow end so the air has to go thru heatsink not around what I did was put a strip of tape across the end so the hole fit the heatsink perfectly. also you need a way to keep it in place don't try using tape for that if the tape looses it contact and duct falls off that wouldn't be good at all. what I am using to keep duct in place is a piece of wire routed under duct and tied to top of case.

 

[Garfield]

I don't fully understand why you took of the fan on the heatsink. Wouldn't that be the best thing to have at the "other" end close to the heatsink?

Do you have any pictures of your duct setup? I'd like to see yours and model mine off of it, or at least get a good idea of what to do. So the duct is sqaure? And then it goes right to the heat sink. Sounds good.

$30. Not bad for lowering temps. How much do they lower?

 

[res0r9lm]

I don't fully understand why you took of the fan on the heatsink. Wouldn't that be the best thing to have at the "other" end close to the heatsink?

Do you have any pictures of your duct setup? I'd like to see yours and model mine off of it, or at least get a good idea of what to do. So the duct is sqaure? And then it goes right to the heat sink. Sounds good.

$30. Not bad for lowering temps. How much do they lower?

I don't have any way of taking a picture but did draw one. intially I got an 8c drop in temps with 60 mm fan on heatsink. since I have changed to the 80 mm fan inside the duct it gave me another 3c drop but the drop depends on how much heat the chip is putting out. I don't really notice much difference between the two ways that I set the fans up at lower speeds and with a lower vcore.

 

[Garfield]

So you just fasten the duct to the two fans by tape? Duct tape? I don't really understand what you meant by using the wire to hold up the duct because tape couldn't do it. Do you mean the duct is almost hanging from the top of the case? I don't understand...

 

[Pat]

I have a 92mm Paniflo L fan on the side of my case blowing in through a plastic freezer container with the bottom cut out forcing the air next to my Swiftech 462-A running a Sanyo Denki 92mm fan.

The plastic container is the same size as the fan & just slips over the fan.

Pat