Question Fan Set-up for my build.....question about fan speeds

mjbn1977

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Please see the parts and specs of my PC below. I do have 2 questions about my fan setup and fan speed settings.

1. Question: I am installing the MSI RTX 4080 Gaming X Trio today in my PC. The card is long but will fit in my case. Currently, I do have two 140mm intake fans in the front of my case. They occupy the top 2/3s of the case. The top one is aligned with the 135mm fans of the beQuiet Dark Rock 4 Pro and the 120mm exhaust fan on the back of the case. The second intake fan sits right below to top one (the case can take either 3 x 120mm or 2 x 140mm in the front). By the way, all my case fans are Silent Wings 3 PWM fans.
Problem. The lower front intake fan sits right middle on to the end of the RTX 4080 which ends just a few millimeters in front of the fan. I either can leave it that way or move the 2nd intake fan down a few inches, so he blows below the card instead on the card (and a bit above and below the card). If I move it down it would blow under the card but also partially against the cable, HDD, PSU bay. What is better, should I leave it the way it is or should I move the second fan down.

2. Question: Fan speeds.....I have two 140mm intake, two 135mm in the tower cooler and one 120mm exhaust in the back. Goal was always to have over pressure in the case to avoid the dusting of all the components. This setup literally accumulated near zero dust accumulation over the last few years. Since the air flow goes from front to back from Larger to smaller fans, how should I adjust the fan speeds. How fast should the fans of the tower cooler run compared to intake fans and exhaust fans? Faster, slower? What would be optimal?

Thanks....
 

mjbn1977

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your concerns should all be based on the current temperatures that your CPU & GPU reach while the system is idling and while in heavy gaming use.

without these stats there is no real good advice to be given yet.

They system had good temp stats before the RTX 4080. Installing today. Don't know yet. But generally speaking, should the lower intake fan blow under the video card or on the video card?