Hi Tom,
There’s a lengthy discussion to varying degrees of success at:
I have 4x250gb SSDs in mine and a RPi 4 8GB. I think at heavy load, the pi is likely to thermal throttle in sustained usage OR have your fans going flat out 100% by default. But this isn’t something I’ve tried because my usage is fairly low for now. Also, to be fair as a NAS, I’d say access is often speradic, a docker server however running sites, uploading, downloading and serving stuff like media round the house may be more liable to push your temps up.
General highlights I’d provide is:
- Reversing the fans helped a little bit, I had to find more bolts to do it and ended up swapping it back.
- Replacing the top fan with a Noctua made it near silent but reduced airflow further, (so as is commented by others in that post) sent their CPU fan higher.
- Adding better ventilation at the bottom and as suggested by others, better sealing the top fan grille around the fan, should cause greater airflow.
- Doing almost all of the above and replacing the CPU fan for just an XL heatsink, seems to have made mine near silent and maintaining 50-52 degrees on the CPU, 38-45 degrees on HDDs which I’m happy with.
I guess, do what you’re comfortable with and start there. It took me at least a few weeks to start doing more extreme stuff with Dremels. And it’s not like you need to do anything, the unit works but the fans are a bit noisy.