HVVHDual Ball Bearings High Speed Durable Mini 4Pin DC 12V 2.7A 6000 RPM Cooling Fan Brushless Replacement Case Fan for Antminer Bitmain S7 S9 D3 L3 E9 T9 etc All BTC Miner Server (2.7A 6000RPM)

Fans slowed down over a week of running. Tested that it wasnt a voltage supply issue also. Airflow is still better than the old fans. Went from 7K RPM down to 6400 RPM in 2 weeks running 24-7. Fans are clean and free of contaminants as well. After slowdown the amperage increased. I'm gonna keep these fans because I dont have any backup fans at the moment but I figure I'd let others know my experience

running 2 of these on an Antminer S9. I've used the tuner to turn the idle speed down to 2400rpm and the noise is very livable. These are advertised as 7000rpm fans and when my miner reboots it pegs the fans to wide open throttle. I'm seeing 6900rpm as indicated by the software and this repeats every time I reboot. With software lag, I think it's reasonable to call this 7000. Anything over 4000rpm causes an ungodly howl. Some of that is my set up but some of that is the fans themselves. Noise is reasonable at/under 3500rpm and at 2400rpm I can sit next to the room the miner is in with the door open and no issue. Noise is important because I'm in an apartment. If it gets too loud, I can't run the miner.

The speed is controlled by the temperature of the machine so if you have to low of a rpm fan then your restricting the temperature from getting cooler. So the rpms are good for my asic crypto miner. The more the rpms are the louder your asic will be just remember that as well.

Good product, happy with the performance, this fan can be attached to a radiator in a liquid-cooled computer.

Fits Bitmain S9. Double check your fan specifications on RPMs however. The fan I was replacing came up as 6000 RPM but I noticed after installation that my fan in back was a 7000 RPM. Ended up replacing the one in back to match.