large case : why GPU cooler type : axial or blower ?

invisiblezombie

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Apr 2, 2011
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Ok, I'm kind of up to speed on how the axial flow fans vs blower fans differ on graphics cards, and where they are best/most effective.

Granted - blower type cards are better suite for small cases with poor airflow so that the rest of the components don't have additional hot air to deal with, and are better suited in SLI config.

Granted - axial type fans cool better in larger cases with good airflow (possibly because they're larger and can have 2 or 3 on a card) and are quieter.

End of the day, the axial flow type cooler does leave its exhaust air inside the case, leaving it up to the case fans to exhaust the hot air from GPU in addition to that from the CPU and rest of motherboard heat sources, which in all likelihood raises the CPU temperature.

Blower type fans will take some of the fresh air and exhaust it out of the case - they may not dump the hot air from GPU back inside the case, but I suppose that does reduce the net amount of air remaining to cool the CPU.

I'm particularly seeking the experiences from folks who have used both reference (blower type) and custom (axial flow) type cooler fans in larger mid and full tower cases , the same GPU chip , if there is any measurable, consistent difference in CPU temperature.

I have an Antec 1100 v2 that's fairly large and airy : 2x 120mm intake fans, 1x120mm rear exhaust , 2x 120mm top exhaust fans, and has room for 5-6 more 120mm fans. I plan to put 2x 120mm fans at the side window to blow air in at the GPU/motherboard when I get my GPU.
I'm more concerned about temps than noise though, being in the tropics, but haven't used any blower type cards before , hence willing to hedge on blower type if there's at least 4-5ºC difference consistently in CPU temperature at load.

The question is - which type will leave me with a cooler CPU (assuming the blower type GPU cooler, even if hotter, is within manufacturer specified limit) ? I gather some blowers are poor and some are excellent, same with axial fans, I'm looking at getting RX480/GTX1070/GTX1080 , depending on pricing and availability here.
 
Solution
Sorry, been playing Doom! 😉

With ambient temperatures that high I'd advise you to stay away from a GTX1080 Founders Edition, even with room temperatures of about 20C when reviewed they ran into thermal limits very quickly, the '1070 isn't quite so badly effected but will still benefit from better coolers, especially in hot climates.
No reviews are in yet (soon, though SOOOOOON!) for the RX480 but I'll guess it'll behave in much the same way.

Bear in mind that not all fans are created equal, there really is a difference between them, especially if you start looking at high quality parts from makers like Noctua and Sythe. It took me ages to find 'just the right ones' for my watercooling loop and I finally settled on the rather bland...
TBH you're worrying needlessly, none of the cards you have in mind are massive heat producers and the case has plenty of airflow, you won't see a really significant CPU temperature change, regardless of what card/cooler you choose.

The only things I will recommend are:

Setup your fans like this: Dual front for intake, rear and top rear as exhaust, don't use a top fan directly over/in front of the CPU cooler (assuming a tower type air cooler) it will slightly increase the CPU temperature, this happened in my Spec 03 case with dual front intakes/rear exhaust/dual top exhaust and a Hyper 212 CPU cooler, by removing the fan directly over the Hyper 212 the overall temperatures dropped, if only by a couple of degrees C.

Don't use a AIO or other liquid cooler for the CPU, unless you're massively overclocking even the little Cryorig H7 or Coolermaster Hyper 212 Evo are more than enough for a stock part and adequate for a mild overclock.
 


I figured I should be well inside maximum temperatures, but there is also component life and stability in mind. Room temperatures in summer can get to high 30s here, and 40s in the open. I've also had an older rig with a 6600GT and later 8600GT crash often while gaming after heating up - it stopped crashing after I removed the side cover. Power wise, the RX480, and GTX1070 are also 150W as the 6600GT. I do have a better case with better cooling now though.

i7 6700k stock with CM Hyper 212X is what I have. I'm seeing a good 29-30 at idle and upto 64 in hottest core with CPUZ stress test, though it's mid 20s now , the hottest days of summer have passed before I assembled the rig. So yeah, I do dread seeing CPU temps hit mid-to-70s in peak summer. I'll keep your advice on leaving top exhaust fans off in mind, will do a measuring runs sometime later with them on and off.
 
Sorry, been playing Doom! 😉

With ambient temperatures that high I'd advise you to stay away from a GTX1080 Founders Edition, even with room temperatures of about 20C when reviewed they ran into thermal limits very quickly, the '1070 isn't quite so badly effected but will still benefit from better coolers, especially in hot climates.
No reviews are in yet (soon, though SOOOOOON!) for the RX480 but I'll guess it'll behave in much the same way.

Bear in mind that not all fans are created equal, there really is a difference between them, especially if you start looking at high quality parts from makers like Noctua and Sythe. It took me ages to find 'just the right ones' for my watercooling loop and I finally settled on the rather bland but otherwise excellent Noctua NF-p14s Redux for the rad, they're also excellent as case fans!
 
Solution


I doubt I'd hit thermal limits on 1080p on the (GTX)1080, in the current games. Anyway, since my rig is all done and only the GPU is awaited , I decided to skip the wait for the AMD RX480. If I had a decent card already I could wait a few weeks more. So ordered a Zotac AMP edition GTX1070. Was thinking of the Zotac GTX1070 FE and they're just $5 apart from where I purchased, but let's see, the custom dual axial fan AMP edition is overclocked and supposedly cool and quiet - and easier to clean off the dust. Few days until it is delivered. I hope it doesn't cause the CPU to run hotter than the comfort zone.