I've read a bunch of posts about making supermicro enclosures quieter, and rather than necroposting, figured I'd start a new thread.
I have several CSE-826 enclosures that are all set up as JBODs with JBPWR2 control boards and BPN-SAS2-826EL2 backplanes, with the fans connected to the backplane, and of course, the stock 94L4 and 126L4 fans which are quite loud, even when they spin down to their lower speed after everything starts up. From my reading, the FAN-0074L4 fans were said to be much quieter, so I ordered three to give them a whirl. Once I swapped the fans into the tan 'caddies' and installed them, when I powered the unit on, they powered on at full speed, which I'd say is roughly the same noise level as the other fans at their reduced speed, but the problem is they never ramp down like the other fans. I was able to get them to run at the lower speed by powering the chassis up with the noisier fans installed, then after they ramped down, swapped them one by one and they continued to run at the lower speed. This of course is not a feasible solution. At the lower speed, the 74L4s are quite a bit quieter. Around 10db it seems. Although interestingly, when I connected them to a SAS-826-EL1 (SAS1) backplane, they DID ramp down. I also found that if I had one of the louder fans in along with two of the 74L4 fans, it ramps down, but this pretty much negates the entire point as the louder fan still makes quite the racket.
I could go with something like the Noctua fans, but the problem with them is they're running half the airflow at full speed (I think they're rated at 34CFM and the 74L4s are rated at 68CFM full speed), which I think should be enough, but if they're running at full speed all the time and an environmental or load change causes some higher temps, they cannot move any more air, whereas if the backplane would ramp the 74L4s down, if it needed more airflow to keep things cool, it's got headroom to increase the speed. I could also go with some sort of external fan controller, but that has the same drawback as the Noctua fans as if more airflow is needed, the backplane can't increase the speed.
That being said, has anyone else had the same issue with the 74L4 fans not dropping to a lower speed after initialization, and if so, was there any fix that would allow them to work right?
I have several CSE-826 enclosures that are all set up as JBODs with JBPWR2 control boards and BPN-SAS2-826EL2 backplanes, with the fans connected to the backplane, and of course, the stock 94L4 and 126L4 fans which are quite loud, even when they spin down to their lower speed after everything starts up. From my reading, the FAN-0074L4 fans were said to be much quieter, so I ordered three to give them a whirl. Once I swapped the fans into the tan 'caddies' and installed them, when I powered the unit on, they powered on at full speed, which I'd say is roughly the same noise level as the other fans at their reduced speed, but the problem is they never ramp down like the other fans. I was able to get them to run at the lower speed by powering the chassis up with the noisier fans installed, then after they ramped down, swapped them one by one and they continued to run at the lower speed. This of course is not a feasible solution. At the lower speed, the 74L4s are quite a bit quieter. Around 10db it seems. Although interestingly, when I connected them to a SAS-826-EL1 (SAS1) backplane, they DID ramp down. I also found that if I had one of the louder fans in along with two of the 74L4 fans, it ramps down, but this pretty much negates the entire point as the louder fan still makes quite the racket.
I could go with something like the Noctua fans, but the problem with them is they're running half the airflow at full speed (I think they're rated at 34CFM and the 74L4s are rated at 68CFM full speed), which I think should be enough, but if they're running at full speed all the time and an environmental or load change causes some higher temps, they cannot move any more air, whereas if the backplane would ramp the 74L4s down, if it needed more airflow to keep things cool, it's got headroom to increase the speed. I could also go with some sort of external fan controller, but that has the same drawback as the Noctua fans as if more airflow is needed, the backplane can't increase the speed.
That being said, has anyone else had the same issue with the 74L4 fans not dropping to a lower speed after initialization, and if so, was there any fix that would allow them to work right?