DIY AMD Radeon R9 290X Heatsink Mod - SemiAccurate
our little mod did conclusively reduce the noise profile of the R9 290X even if it didn’t boost performance
they kinda did it wrong, though, they should have measured temps and fan RPMs. You’d be surprised how much backpressure there is from vented metal:
Feeding My Graphics Card Addiction
I cut half of the rear plate away with a dremel, which immediately reduced fan speeds 20% (and thus, noise 20%) due to the improvement in airflow.
And
http://www.silentpcreview.com/forums/viewtopic.php?t=15810
Wire grills also have an effect: ~20%. This was checked with an anemometer on several different fans of 80, 92 and 120mm size, at full and lower speeds. The airflow reduction went as high as 24% but it was never below 19%
I’m gonna have a damn dremel field day with this thing. And it’s gonna be glorious.