Now that I have both a Turbo Color and Turbo Mono machines, I would like to see what I can do to make them a little quieter. My understanding is that the Turbos use a faster (and louder) fan over the 25MHz versions - both of mine have a 5,700 rpm fan (80 cfm!). Even though I have SCSI2SD instead of a physical hard drive, I don't think I can get away with replacing the fans with something like a Noctua 2,000 rpm fan that only does 30-32 cfm. Has anybody found something closer to the original fan that's actually quieter? Thanks!
So would it be safe to say that nobody has ever replaced a Turbo fan?
Hello Polbit: I've had good success with Artic Cooling fans .
https://www.arctic.de/us/products/cooling/case-fans/
Quote from: Rob Blessin Black Hole on April 19, 2022, 10:44:54 PMHello Polbit: I've had good success with Artic Cooling fans . https://www.arctic.de/us/products/cooling/case-fans/
Hey Rob, unfortunately none of these flow more than 31cfm, same as Noctua. 68040/33 is a pretty hot chip, just a little apprehensive about using a fan with less than 1/2 of thermal performance.
Quote from: polbit on April 21, 2022, 05:31:23 AMHey Rob, unfortunately none of these flow more than 31cfm, same as Noctua. 68040/33 is a pretty hot chip, just a little apprehensive about using a fan with less than 1/2 of thermal performance.
Never had an issue and it's been many years...
https://www.flickr.com/photos/t-rexky/6795424356/ (
https://www.flickr.com/photos/t-rexky/6795424356/)
Quote from: t-rexky on May 27, 2022, 05:22:24 PMNever had an issue and it's been many years...
https://www.flickr.com/photos/t-rexky/6795424356/ (https://www.flickr.com/photos/t-rexky/6795424356/)
Again, that fan is less than 1/2 of CFM than the original TURBO fan. 68040 get really hot in general, and 33MHz runs MUCH hotter than 25MHz. Steve Jobs was always a big fan of quiet, so if they put that loud of a fan in the original machine, there had to be a reason...
The SCSI drive is the biggest contributor to heat build up in the machine.
Quote from: barcher174 on May 28, 2022, 11:15:50 AMThe SCSI drive is the biggest contributor to heat build up in the machine.
That is a good and obvious point that I should have thought about. I guess a 2-4W CPU is not that big of a problem next to a 10W mechanical SCSI drive.
Alright, my Noctua fan is going in, thanks!
I'm not a specialist on the NeXT airflow layout but I am pretty good with airflow generally.
68030s don't need an HSF combo, but they do benefit from one in confined spaces.
68040s do run a lot hotter at higher speed grades, and absolutely benefit from an HSF. One of the best ways to cool off one of those systems is to use the highest speed grade of '040 under-clocked to the normal speed of the board. Another is to use an LC or EC version, IF the system used doesn't need the MMU or FPU.
That said, the 030 and 040 are surprisingly tolerant of abuse up to about 85 or 90C.