- May 29, 2013
- Asus Z370-G Gaming (Wi-Fi AC)
- i9-9900K OC'd @ 5.0GHz
- RX 6600 XT
- Classic Mac
- Mobile Phone
Looking at that case, I suspect that a negative pressure setup would work better for the open cooled GPU, particularly because if means reversing the airflow from back to front.
Without any case fans at all, the air from the GPU (and CPU) would rise to the top of the case (between the PSU and disks), and as it cooled, it would spill over the top and fall behind (under) the MB. You would end up with internal airflow rising in the big part of the case and falling in the small gap under the MB - especially if the GPU and CPU fans were stopped.
With your current positive pressure setup, the cool air from the front will be split. Most will be directed through the CPU cooler and exhausted through the back, but a significant amount will pick up the hot air from the GPU and blow it round the case, probably following the natural air flow path, so you end up heating the MB from below and then have hot air mixing with the air going through the CPU cooler - bad all round.
That natural motion will happen whenever a fan can't prevent it. In your case, most air from the GPU will rise in that area. The exhaust fan will only deal with the air from the CPU cooler and the front case fans, which means the GPU heated air will be forced back into the general airflow in a position where it will come through the CPU cooler. On the way, it will be heating the MB.
If you reverse the case fans, the CPU gets pure external air, so should have the best temps possible. The GPU heated are will be drawn to the front of the case, and even if it spills over the top, that air will also be drawn to the front before it can heat anything else.
With the closed blower cooler, you have no GPU heat remaining in the top of the case, so the air moving round the case helps cool the disks and MB instead of heating them, resulting in good cooling all round. Because the GPU air is being exhausted at the back, you want your current front to back airflow to prevent the GPU air being sucked back in again.
Hmm... Interesting... I didn't think that the positive pressure could be detrimental... I always thought that compressing more air in to the case would cool the air and help all components.
I can see how using the two front case fans to suck out the heat from the case might help. However, don't you think that the fans on the video card would still force the hot air generated from the video card downward towards the CPU cooler?
I'm trying to envision in my head how changing direction of the airflow and creating a negative pressure situation would work. I think for it to be effective, I'd have to reverse all the case fans and the two CPU fans. I'd also need to rethink dust management. Alternatively, I think I can do a quick, albeit less efficient, test simply by unplugging the two front fans.
Reversing all the fans will require a considerable amount of time due to how tightly everything is packed in right now. I'd also have to saw off a corner of the rear fan so that the Wi-Fi/Bluetooth card to fit. So, this test will probably have to wait until the next time I pull everything out to mess with my Z390 motherboard again.