My CPU cooling hit a dead end - fan speed make 0 difference

[ilovecats]

Try testing with case laying flat, side open and fan turned over so it is drawing air out of CPU cooler. I have often seen this lower temps but 5c+.

I think this is caused by the air blowing onto mobo > hitting RAM, GPU, I/O housings, etc. > coming back alongside of cooler and being sucked back into fan.

Thanks for the idea. What do you mean by the "fan turned over" though?

I kind of suspected it was the tight "box" created by the bottom panel, the GPU and the RAM walling the heat in. But I thought the front intake fan should have provided some fresh cold air to the cooler, and the exhaust fan (previously on) should have helped sucking the heat out. But neither ended up making a difference. That's why I'm at a total loss.

 

[doyll]

Pull air out of cooler instead of pushing air into cooler.

Unclip the fan from cooler, turn it so the side that is showing now against the cooler and clip it back on.

Even on open bench tests I've found this usually give lower CPU temps.

Edit:
Look at post #13 in this thread
http://www.overclockers.com/forums/showthread.php?t=724638

 

[johan851]

Well, try turning the fan down to a low RPM at one of your lower temps. If your temps go up turn the fan back up or shut it down. If you see different temps, then your sensors are working fine. You might just be hitting diminishing returns on the fan. You haven't tested a particularly wide range, though I'd expect some difference between 1200 and 1800 RPM too.

 

[ilovecats]

Pull air out of cooler instead of pushing air into cooler.

Unclip the fan from cooler, turn it so the side that is showing now against the cooler and clip it back on.

Even on open bench tests I've found this usually give lower CPU temps.

Edit:
Look at post #13 in this thread
http://www.overclockers.com/forums/showthread.php?t=724638

Thanks. Will try when I get the chance. So if you use the CPU fan as an exhaust, does static air pressure still matter now that you don't need to penetrate air into the fins?

 

[johan851]

Sure. You're still moving air against resistance, you're just pulling it through the fins instead of pushing it through.

 

[doyll]

Static pressure is the difference in pressure from intake to exhaust side of fan. Pulling air creates a vacuum on intake side of fan. This vacuum pressure to exhaust pressure of fan is about same as fan's pressure buildup is when pushing air into cooler.

Edit:
It's possible that the reason you are not seeing any difference from 1200rpm to 1800rpm is because as the fan increases in speed it is sucking more of the heated air that is coming back along the sides of cooler back in.

 

[ilovecats]

Thanks for all the help. I realized though that if I were to put the fan upside down, that would have defeated the entire purpose of using a top-down cooler. I think I should have just stick to the good old hyper 212 plus pushing the hot air out of the rear exhaust and I'm pretty sure my temp would have been 10C lower. Instead I spent $60 just on fans lol silly me.

 

[doyll]

Turning the fan over does not defeat anything.. and if it improved your cooling you win. What have you got to loose? It isn't complicated or time consuming to turn the fan over and see if it improves cooling.

Obviously it's your decision to try it or not... but first take the cat out.

 

[ilovecats]

Turning the fan over does not defeat anything.. and if it improved your cooling you win. What have you got to loose? It isn't complicated or time consuming to turn the fan over and see if it improves cooling.

Obviously it's your decision to try it or not... but first take the cat out.

I meant the "blowing at the motherboard to cool VRM" aspect.

Yeah I will try it out though.

 

[doyll]

I had lower VRM temps with fan sucking air up.. cool air moving toward bottom of cooler instead of hot air coming out of cooler.

 

[ilovecats]

It turned out...doyll was completely right! I mounted the original Enermax CPU fan upside down, put the AP-14 on the rear exhaust, and voila, the CPU temp dropped 4 degrees, motherboard dropped 1-2 degrees as well. Thank you so much!

 

[azanimefan]

It turned out...doyll was completely right! I mounted the original Enermax CPU fan upside down, put the AP-14 on the rear exhaust, and voila, the CPU temp dropped 4 degrees, motherboard dropped 1-2 degrees as well. Thank you so much!

i'm glad it worked. now find yourself a hyper evo 212 (or something better even) and stick it on, facing your back exhaust, and watch temps drop like a stone. Those flat heatsinks generally perform poorly no matter how much money you spend on them for a reason.

 

[doyll]

Flat heatsinks perform poorly because hot exhaust air mixes with cool intake air. Tower cooler tend to do a better job of keeping the hot exhaust away from cool intake.

 

[ATMINSIDE]

Your case will fit a Noctua NH-D14, that'll drop your temps

 

[ilovecats]

Yeah I originally didn't go for NH-D14 because it was too expensive. I ended up spending more with the fan upgrades though!

 

[ATMINSIDE]

That's why you find a used one

One of the guys on here is selling one right now, let me find the thread.

Edit: http://www.overclockers.com/forums/showthread.php?t=733713

 

[Conumdrum]

He hasn't been here long enough or have the required 100 quality posts to access the classies.

 

[ATMINSIDE]

Oh yeah...

 

[ivanlabrie]

He can still hit overclock.net marketplace...an aio or a tower cooler would be better, but won't make too big a difference if the cpu's ihs to die heat transfer is not ideal. (being an ivy bridge cpu that's normally the case)

 

[ilovecats]

He can still hit overclock.net marketplace...an aio or a tower cooler would be better, but won't make too big a difference if the cpu's ihs to die heat transfer is not ideal. (being an ivy bridge cpu that's normally the case)

Seriously, several times I almost made up my mind to do the IHS thermal compound mod, but eventually stopped myself because I *know* I will break it. I'm not good with knives and craftsmanship.