Open air vs blower GPU for SFF

[Ruahrc]

I am thinking about upgrading my GPU as it is going on 3 years old now. One aspect to be considered is open air vs blower style cooler.

The GPU I have now is the open air style (6950 Twin Frozr III) and although it has been fine I wonder if this time I should try a blower? I was honestly a little disappointed in the TFIII cooler as I felt it had more audible fan noise than I expected, which meant I had to apply a very aggressive fan profile to keep it quiet under gaming loads.

I read that blower style is better for small cases with limited airflow, but I also know they are generally louder than the open air designs, especially at load. However most reviewers report noise levels when testing GPUs in full cases or even in the open air, so it is hard to know if their results are directly applicable to SFF situations. Noise is a significant factor when I design/select my components, so I am curious if I should try the blower style GPU. It seems like the only situation where a blower would have an advantage is if an open air style GPU was so starved for case airflow/cooling that it had to ramp its fans up much higher than the blower would just to keep steady temps.

Looking at my build I have Lian Li PC-Q08 with some part swapping (Noctua fans vs. stock). Looking at the layout (you can see my build report here: http://hardforum.com/showthread.php?t=1639617) I am not convinced a blower GPU will do me any better? The GPU is sucking cool air directly through vents in the bottom of the case. There is 140mm inlet fan blowing into the case, and 120mm outlet fan exhausting directly out the top. I removed the HD cage from the PC-Q08 which really allows direct airflow from the inlet fan into the case.

I do not notice any real temp issues in my case, my CPU never really goes above 50C, and my GPU is usually between 60 and 70, depending on the game. Based on this I don't think the blower GPU will actually be any better in terms of noise in my situation. Do you guys have any thoughts?

FYI the card I was looking to get was the EVGA 770 SC with ACX cooler. Or maybe the Gigabyte 770 with the triple fan setup (it was reported by Anandtech that the Gigabyte had the lowest noise)

Ruahrc

 

[BenWah]

I decided against blower because they're so much noisier.
With that 140mm noctua you've got hurricane of cooling going that will change the air out so fast.
I went with gtx 770 msi twin frozr.

 

[Skott]

Noise can be subjective too. What one person considers loud another person may think is not so bad. Tolerance levels vary from person to person. Some people can be down right anal retentive about noise coming from a PC. I have a buddy like that. The PC can be pretty quiet but he'll think its too noisy and get himself all worked up about it.

 

[matman]

I have put a lot of thought into this topic and have come to the conclusion that most SFF designs are wrong. So many have some kind of disclaimer about blower GPUs being the better choice. The real solution is to design a case that actually permits free flow of ambient air directly to the GPU AND allow a clear exhaust path straight back out of the case.

The best GPU air cooling solutions around lately are vertical fin heatpipe designs (eg Windforce 3, Tri-X) that exhaust heat vertically (assuming a horizontal motherboard) mostly upwards, some down. Considering the majority of SFF buyers are more noise conscious than your average enthusiast I'm amazed that none of the small case builders have thought to allow for clear exhaust flow from the best cards. Worse it seems to be acceptable to jam hard drive mounts where there should be ventilation.

If it were my Q08 I would cut full length ventilation openings in the bottom and left panel. With those mods I'd be very surprised if the whole case wasn't both cooler and quieter than a blower config with no mod.

To be fair I do have a history of taking graphics ventilation to extremes.

 

[cowsgomoo]

I had an AMD blower card and I'll never use one again. My components can bake themselves for all I care.

 

[WiSK]

I have put a lot of thought into this topic and have come to the conclusion that most SFF designs are wrong. So many have some kind of disclaimer about blower GPUs being the better choice. The real solution is to design a case that actually permits free flow of ambient air directly to the GPU AND allow a clear exhaust path straight back out of the case.

I agree this would be ideal, but it's tricky to make a practical solution.

The obvious bit is to have vent holes in front of the card's fans, and along the whole panel. Although if a card is much shorter than the vents, there can be a bit of feedback here, as hot air gets sucked out of the case because of the negative pressure at the vents. (I had this issue with a Phantom 560ti in a SG05). So you need a kind of slider to close some of the vents if needed.

Then where does the air go? For dual fan GPUs, the air is blown out the edges of the card, on all four sides. So hot air goes not only over the top of the card into the motherboard area, it goes under the motherboard as well. So you need a partition that keeps the air compartmentalised from the motherboard. But this is not enough, that space would become much hotter with only GPU intake. So you need extraction fans above and below and maybe at the end of the card (like SG10 has a little 80mm extraction fan at the front for this purpose).

Practical problems is how to make a partition that fits and closes off all possible GPUs that people may use. Another difficulty is the fans. Where to put them in limited SFF space? What sizes to use? Since many mITX boards only have two fan headers - how to control these extra fans to be silent?

 

[Necere]

I agree as well that having a more coherent, direct path for air is ideal - the problem comes in trying to do that in an SFF system, without getting very specific about the kind of components you have to use. The shape, size, and airflow requirements of different components don't lend themselves to very compact layouts. Just taking the M1 as an example, since I have a bit of experience with it *cough*, keeping the same hardware flexibility while incorporating a more direct airflow path with decent-sized fans would've increased the size by ~50% or more. And you know, there's a part of me that thinks that's not a bad tradeoff for better thermals and noise. But the M1 had some specific design goals, which that compromise wouldn't have coincided with.

 

[Ruahrc]

Thanks for the input. I decided against the blower style GPUs and ordered an EVGA 770 with ACX cooler. Can't wait for it to get here!

 

[sgtspiff]

(the post should be read as written with interest and curiousity)

I've never used a graphics card with fans but a need to get into the discussion.

Blower style cards are such a smart idea if it weren't for the simple noise problem. They get the hot air out of the case.
Open Air is just a redistribution of the air inside the case. So I say it's just the same as a passive version of cooling.
So as said above by everyone else (yes I'll bring yet again almost nothing to the discussion) it's all comes down to case airflow. And as an owner of the same PC-Q08(R) as OP I just feel the flaws of older ITX design and general GPU design.

I firmly believe that GPUs should be redesigned to be the same version of processer as a CPU. Simply another socket on the motherboard. Use twincoolers that cools both processors att the same time.
As this never will happen alternative 2 is:
Skip the coolers on GPU when you sell them (just as processors, or boxed versions) and let the 3rd party producers take forth great coolers (as Arctic).

For the ITX cases (using my case as reference):
1 fan in, at the front.
1 fan out, at the top (CPU)
1 fan out, at the bottom (GPU)

Ramble incoherrently, Sgt. Spiff

 

[Deleted member 258125]

What would you recommend for a closed bottom case like Lian Li's PC-Q11 or PC-Q07? Rather a blower or dual fan setup?
And what about good ol' SG05? I have seen a variety of GPU choices but I'm not quite sure what would be the best this being a more openly designed case.

 

[Unknown-One]

Thanks for the input. I decided against the blower style GPUs and ordered an EVGA 770 with ACX cooler. Can't wait for it to get here!

Good luck. From my experience, the ACX has issues at low RMP (the fans whine really badly below 40% fan speed). I've RMAed 5 times now, and they all have whine... about ready to give up on EVGA ever getting it right.

The reference blower cooler that comes on the 770, 780, and Titan is far, far quieter.

 

[fr500]

Mine is totally silent

 

[Unknown-One]

Mine is totally silent

My sample size is larger (and growing, since I just RAMed another whiny ACX cooler)

I'll let you know if EVGA ever gets it right. Not looking good so far.

 

[Ruahrc]

Good luck. From my experience, the ACX has issues at low RMP (the fans whine really badly below 40% fan speed). I've RMAed 5 times now, and they all have whine... about ready to give up on EVGA ever getting it right.

The reference blower cooler that comes on the 770, 780, and Titan is far, far quieter.

I got my card and installed it a few days ago, so far I'm quite happy with it. I do wonder if I should have gone with the classified edition which looks like it has the same fans but larger heatsink, however I think it would have been basically the same in the end.

I do not have any whine at 40% (which seems to be the lowest I can make the fans go) and it is virtually inaudible at this speed. Furthermore, the character of the noise is better than my old GPU fans which had some whine/buzzing. I do hear a tiny bit of coil whine from the card at idle though.

As the temps rise and the fan speeds up, again still no whine, but you do hear increased "air whooshing". This becomes the dominant noise from my case (the rest of my fans are very quiet) but again it is not very unpleasant in character (nor is it really all that loud). This is better than my old GPU whose fans increased in whine as the RPMs went up... about 45% on the old GPU and the fans developed a distinct pitch.

As I understand it, the reference cooler is extremely silent at idle. Because of the low RPM and single fan. However, under gaming loads, the single fan on the reference cooler needs to ramp up higher and is louder at load (which is what I care about more) than the dual fan designs, which can keep the fans at lower rpms.

I'm still playing around with tuning the fan profile to quiet it down under gaming load. I am also trying to get it to undervolt using MSI afterburner- it seems like you have to "trick" the card into doing so by limiting the power and then raising the core GPU clocks so it keeps reducing the voltage to stay within the envelope? Not used to managing a GPU that auto boosts itself.

I dunno though running ARMA 3 it never seems to go past 60-70% power used so even though I have it turned down from 100% to 80% it still does not hit its power limit. Temps stay in the 55-60 region too which seems pretty good.

 

[Unknown-One]

I do not have any whine at 40% (which seems to be the lowest I can make the fans go)

40% is about where the whine finally cuts out.

GTX 780 allows fan speeds as low as 26%, and there are multiple speeds between 26% and 40% where the fan makes horrible whining noises.

and it is virtually inaudible at this speed.

That I'd disagree with. The ACX is far from silent at 40% fan speed.

The reference blower at 26% is much quieter, and I'd love to run the ACX at 26% to compare, but it picks up a severe whine that makes the reference blower the clear winner.

 

[Ruahrc]

I'm not going to dispute your experiences, there are just too many variables at play. I'm sorry you were not satisfied with the ACX.

GTX 780 fan goes down to 26%, is that reference cooler right? I can't imagine the ACX units on different models of card will have different fan limits.

Interesting experiences here with AC3. The temps are much higher when running this game, although the power limit still does not quite hit 80C. I was testing with Arma 3 earlier since I felt that was the most demanding game I had. Maybe my results are biased by the game being CPU bound on my system? (I did not see massive FPS gain with the new GPU... although it did allow me to turn everything up to very high/ultra with no penalty. I kept disabling/enabling different graphics options and none of them really had any effect on my frame rates)

Anyway I tweaked the fan profile to be a little more aggresssive on noise (i.e. lower fan speeds) and don't really notice any difference in temps or performance.

Ruahrc