Does case airflow really matter much?

[maizenblue]

I have a friend with a liquid CPU cooler and a GTX 780SC that has a stock heat sink fan that vents out the back of the case. With that setup airflow from his case seems almost irrelevant. If you play a demanding game like BF4 at 1080p that GPU card fan ramps up and seems to do all the work of keeping the card cool while venting it out the back, regardless of case fan settings, while the liquid cooler keeps the CPU cool. The case fans seem to have very little if any effect on temps.

 

I mean if you put a side panel fan on the case and filled every other mounting spot with fans going full blast, would it really matter beyond maybe slightly decreasing the RPMs of the GPU fan(which I admit sounds like a jet engine on full blast).  Would that have any noticeable effect on the life and performance of the GPU, CPU, or motherboard?

 

It seems like experienced PC builders don't worry much about case airflow and just focus on looks and other features, and all this obsession with air flow and air cooling in a case is largely a waste that has no noticeable effect unless you are doing an air cooler and have a GPU with fans that vent inside the case.

 

Am I wrong on this?

[DoubleY]

It help keeps HDDs, motherboards, RAM, VRM Heatsinks, and various other things cool. 

[flibberdipper]

Yes. A million times yes.

[Jade]

Yes. Else you run into thermal throttling and effectively make your machine as powerful as a potato (console).

[Internet Swag]

It matters, but it's overrated. 

 

Running my fans at 30% vs running my fans at 100% in a case with 8 fans I barely get a 3 degree temp difference. 

[D3MON]

its a good idea to have some cold air in the front and some hot exhausts out the top or back, but its not worth going out and buying 5 £10 120mm fans (noctuas or corsairs etc) for and filling your case and dealing with all the wiring, as i speak im testing a hyper 212 on a bulldozer 8120 @4.2ghz 1.425v in a nzxt source 210 with the rear exhaust fan and no intakes,
  under stress test the most ive seen is 66*c so i can still push further (or reduce voltage, it did boot at 4.5) which for a compact case (considering what tis filled with) and an xfx 6870DD id say is good eveidence that its not something that you need to worry about too much.....unless your actually having problems or unless you like in india and its 30*c ambient (24*c here).

what im testing in (with the fan the other way round and both side panels on)

hardly the king of airflow.

-though i will say smaller more densly built systems require more airflow (cm elite 110 for example), airflow doesnt really matter if your running an itx system in a 900d...the next step up from that is your room and a test bench, a test bench in a room is the world biggest case (maybe a Ras Pi in the royal albert hall?)

this needs lots of airflow (304 with lots of hard drives packed together)

this not so much.....

[ForsakenLive]

It makes a huge difference, not only in noise, but also performance.

A good airflow case, can make a 15°C difference in both GPU and CPU temps, against case with restricted airflow.

GPU and CPU temps are not all that it is to it, HDD, RAM, Motherboard, and even the PSU, gets affected in performance, stability and lifespan.

'experienced' builders are companies (and shops) that try to make costs as small as possible, and it's good for their business to have you there looking for support, earlier than expected.

its a good idea to have some cold air in the front and some hot exhausts out the top or back, but its not worth going out and buying 5 £10 120mm fans (noctuas or corsairs etc) for and filling your case and dealing with all the wiring, as i speak im testing a hyper 212 on a bulldozer 8120 @4.2ghz 1.425v in a nzxt source 210 with the rear exhaust fan and no intakes and under stress test the most ive seen is 66*c so i can still push further (or reduce voltage, it did boot at 4,5) which for a compact case (considering what tis filled with) and an xfx 6870DD id say is good eveidence that its not something that you need to worry about unless your actually having problems or unless you like in india and its 30*c ambient (24*c here).

I agree with this, people buying 8 noctua fans because they think they need them is silly. I mentioned on my answer that airflow is very important, and it is. But to have good temperatures, you also need an efficient thermal design. A case overloaded with fans, it's not going to make a difference if the design is not efficient, you can have 8 fans, but if the air near the important hot components is not taking benefit of all that airflow it becomes useless. You can have a small and very efficient well ventilated small form factor enclosure, and have outstanding temps.

A good example would be a case like the Cooler Master N200, it's compact, but if you mount enough fans it becomes a efficient cool little box.

[D3MON]

I agree with this, people buying 8 noctua fans because they think they need them is silly. I mentioned on my answer that airflow is very important, and it is. But to have good temperatures, you also need an efficient thermal design. A case overloaded with fans, it's not going to make a difference if the design is not efficient, you can have 8 fans, but if the air near the important hot components is not taking benefit of all that airflow it becomes useless. You can have a small and very efficient well ventilated small form factor enclosure, and have outstanding temps.

A good example would be a case like the Cooler Master N200, it's compact, but if you mount enough fans it becomes a efficient cool little box.

thanks man, redid my post if you want to use it as an example of what you said. (thermal density  FTW)

-ooh never saw that case before, will look it up, cheap 350d rival maybe..

[ForsakenLive]

thanks man, redid my post if you want to use it as an example of what you said. (thermal density  FTW)

-ooh never saw that case before, will look it up, cheap 350d rival maybe..

Just saw your edit. 

The design of the case and the airflow it's what matters, as your examples show.

On the first picture, adding more fans can potentially cool things better, but the difference won't be as much, expect 1-3°C, unless the user lives on a very hot environment.

The second picture doesn't show a Node 304, I can't tell what case that is. But it's pretty packed, and the design will need a bunch of high performance fans. The last picture makes me lol.

Check out the N200, for a mATX budget system, it's hard to recommend another case, even the Fractal Core 1000 sits behind, it has less ventilation and a ugly top PSU. Pricing is pretty similar.

[maizenblue]

So what is an acceptable temp for a GPU to run consistently at under full load? I focus on GPU because its the most expensive component in my PC by a large margin. I know for EVGAs precision X you can set the fan speed on the GPU to keep the card under a certain temp(or reduce the clock speed to keep it under a certain temp). Using automatic settings my GTX 780SC runs at about 72C with the fan speed at about 70% when Im playing BF4. Is that an acceptable temp or should I increase the GPU fan speed? I have a graphite series 230T case that has the fans running 100% all the time. If I let the card do its own thing it lets the card hit 80C. 80C seems a little hot to me.

 

Again, at least with this GPU the case fans seem largely irrelevant and temps are basically changed by my GPU fan settings.