Hi! I currently have this build using the GT502 case.
I just recently got 3 more case fans. Previously it was set up like this:
I think that for some reason the temps got worse and the PC much louder. It might just be buyer’s remorse but I got more fans so that they could use less RPM and be quieter, but I feel like the complete opposite has happened.
Can I change anything about this layout to optimise airflow? I was thinking of maybe switching the side panel fans to exhaust? That might starve the CPU cooler, though…
Maybe I’m just imagining things and I just need to perform exact tests to figure it out. What do you use for testing airflow effectiveness?
UPDATE:
The issue was weirder than I would’ve thought. The bottom 3 fans are controlled by one motherboard channel using a PWM splitter cable. The rear and side panel fans are the same - one channel for all 3. Previously I had just the rear exhaust plugged in to a single channel but now it’s plugged into the splitter.
Apparently the order of the fans in the splitter is VERY important. I changed it so that the rear fan is the first in the splitter and that instantly fixed the issue. ¯\_(ツ)_/¯
Is the top mesh or solid? I can’t tell.
Very loud noise/vibration typically means too much positive pressure, the fans are fighting each other.
If mesh you shouldn’t be having any problems with rear exhaust and the rest intake… I’d just tune the rear exhaust to match the cpu fan and run the rest on a much, much less aggressive ramp up.
If solid, leave bottom 3 intake, rear exhaust, side two exhaust. This leaves the air pressure net balanced but keeps air flowing consistently up through the case. The gpu will get plenty of fresh air, the side two exhausts takes care of the gpu air, and the rear exhaust will ensure there’s a natural flow towards the cpu cooler and won’t starve it.
The top is mesh. That’s why I did so many intake fans - to let the pressure naturally out of the top.
I still might experiment with switching the side panel to exhaust. That’s what I wanted to do in the first place but every build I saw used it as an intake and I was scared that would starve the CPU fan.
I did seem to get the noise down a bit by modifying the curves and making the ramp up smoother.
Yeah, less speed always better… Generally mesh should be a near-zero backpressure flow thru but with this number of fans its still a lot. even with mesh though I think you might get better performance by changing the two side fans to exhaust. It’s worth trying and costs $0.
Most builds use those as intakes because they don’t run bottom fans, either for aesthetics or because GPU clearance is a problem.
That side panel is also the most popular spot for AIO/custom water radiators l, which should also be an intake as to feed the rads cool air. But in your case you don’t need those so running them as exhaust is fine.Generally computers are way less sensitive to airflow than you think. Air kinda just goes where it needs to based on the changes in pressure. Keep trying configuration and fan curves, run a stress test each time for 10min or more and monitor your cpu temps, you’ll likely see they only changes 2-3c at most across all sorts of different fan flow patterns.
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Wow, thank you for such a great explanation!
I will probably first try switching the side panel fans to exhaust, just because it’s much easier and might help level out the pressure. If that doesn’t work, I’ll definitely try your proposed layout!
Late to the party, but if you do turn your bottom fans around, remember to keep the desk/floor/whatever your PC is on clean. We can all pretend to actually clean the bottom filters regularly, but we know that’s not true and the filter will turn into a wall in a few weeks. Also why my only intakes are on the front where the filter is just magnetic.
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The easiest hack for testing airflow is to burn an incense stick and see where the smoke goes.
This reminded me that I too probably have a bad airflow.
I did optimize curves for silence when not gaming but with helldivers I noticed I am hitting just a bit too high temps on CPU then I am used to.
I have two 140mm front coolers, and 240 liquid top-mounted CPU cooler (2x 120 coolers, pushes air out through the radiator), no exhaust fan but the fractal north case has pretty open back side so the theory was that whatever extra pressure there is it’s going to out the back but I think the front intake fans might not be configured properly (3080 and lightly undervolted 13900kf).
I’d make the back and bottoms intake and exhaust on the side with that config.
Or intake on the side and exhaust in the back and bottoms.
Or mouth the side ones on top as exhaust if possible.
Back intake means your are fighting the airflow from the CPU cooler unless you switch that one around, too, and pretty much reverse the whole airflow in the case.
Don’t think that makes too much sense. Cases these days seem to follow a “front in, back/top out” airflow philosophy anyway.
Wouldn’t a back intake make the CPU cooler useless? I would need to switch the CPU fan to the other side which I’m not sure there is enough space for.
Exhaust in the bottom seems like it would do the same thing - starve the GPU fans of fresh air.
Top exhaust, though, might be better. 🤔
