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If it helps, I found that for my LZX-8 with hex hole patterns for the front fan intake, when mounting a NF-A15 HS-PWM causes less turburlence compared to an Artic P14. Come to think about it, previously when using Thermalright's fans instead, the TL-D14S (140mm fan with 120mm mounting holes) compared to the TL-C14S (standard 140mm fan), the D14S has less fan turburlence as well.What I have found, for a different case (with a similar layout), using the following nut and bolt to use as a spacer does eliminate most of the turburlence, but your mileage will vary I reckon, as the panel thickness might make a difference.
If it helps, I found that for my LZX-8 with hex hole patterns for the front fan intake, when mounting a NF-A15 HS-PWM causes less turburlence compared to an Artic P14. Come to think about it, previously when using Thermalright's fans instead, the TL-D14S (140mm fan with 120mm mounting holes) compared to the TL-C14S (standard 140mm fan), the D14S has less fan turburlence as well.
What I have found, for a different case (with a similar layout), using the following nut and bolt to use as a spacer does eliminate most of the turburlence, but your mileage will vary I reckon, as the panel thickness might make a difference.