Question Airflow help for watercooled 1000D build

Oct 25, 2021
TLDR: CPU AIO 420mm radiator and fans in top, custom loop of two 360mm radiators and fans in front with 240mm radiator and fans in rear for two 3090's. How should I configure airflow?

I recently purchased a 1000D to house a 9900K with two 3090's in it. I primarily game on it, but when I'm working or not gaming, I've got it mining (hence the second 3090).
The first 3090 originally had a hybrid cooler on it from EVGA. The second 3090 is an FTW3 and it had the 3 fan oversized cooler on it. When i was running just the hybrid 3090, I could mine with the side of the old case closed and temps were under control. Adding the FTW3 complicated things as its placement was blowing hot air directly onto the hybrid. I ended up buying the 1000D to have more room in the case and hopefully solve the issue. It didn't really...So I ended up building a custom loop for just the GPU's because i had a brand new 420mm AIO cooling my CPU.
New loop is two 360mm radiators on the front. I had considered 2x480 but I think I'm glad i didn't - the tolerances with the EKWB radiators and the front mount were disgusting and I ended up having to offset the radiators to get them to fit - one sits at the bottom of the radiator tray, and the other sits at the top. There is a 240mm radiator on the rear as well. My layout is: Pump > 240mm radiator > GPU > GPU > 360mm rad > 360mm rad. Coolant temp sits around 48c with the side of the case off.
When I put everything together at first, I had the AIO in top as exhaust, i had a 140mm and 120mm fan in rear as intake and the front 6 fans were also exhaust. I was obviously not getting enough airflow to keep things cool and when i'd close the case, it would start to get rather hot. I swapped the 6 in front to intake but when mining, everything is so hot that it would start heating up all the other components in the case when the side was closed. I swapped the top AIO fans to intake but since there is less total airflow than the 6 120's up front, it didn't really do anything, especially since its warming the air as it passes through the top radiator.
With the front intake fans, one set of them is directly blowing on my coolant reservoir and while the coolant is warm from the GPUs. I know having hot air blown on it from the radiator isn't helping. I last week added the 240 radiator in the rear to see if this might help lower my coolant temps further. It doesn't really seem to have made a significant difference.

I realize that by mining, I may end up having to leave the side of the case off to keep things cool. But I'm not sure what anyone else thinks is the best way to manage the airflow is in this system.


Take some pictures of your setup - remove the side panel glass so there's no reflections. Post images via
One of the few people around here who dabble in custom loop may see something you might have missed.
You should also add what kind of thermals you're experiencing. Things are kinda vague as is.