MiSTer FPGA Forum

I just got a pre-built Ultimate MiSTer that came with a Noctua fan pre-installed. I noticed after having the device on for a while that the fan wasn't running. In fact, I've never actually seen or heard the fan come on yet. Is the fan supposed to run "full-time" or only turn on when it gets hot?

The IO board should have a jumper to set the fan voltage to either 5v or 3,3v.
It´s right next to the fan header.
Could have fallen of/forgot to install during building so check that it´s there.

If the fan is finicky, it may need 5v to startup. Try the 5v jumper position if it is on 3.3v (or missing entirely).

In addition to what ash said, an explanation of why fans may not start or may have issues if their voltage is too low is in this Technology Connections video.

https://www.youtube.com/watch?v=hQ3GW7lVBWY

Essentially the fan needs enough voltage to "turn over" similar to a starter on your gas-powered automobile. If it can't get started easily enough, it could sit there collecting electricity and burning.

However, the noctua fan they use IS designed for 3.3v so I highly doubt that is what is causing it to fail, that it's not enough voltage to turn over. It's likely that one of these things is happening:

1. The fan is faulty

2. The connectors going to the jumper pins are not making a consistent contact.

3. That I/O board is faulty

4. The connection from the I/O board to the DE10-Nano is faulty.

grizzly wrote: ↑Tue Nov 03, 2020 12:43 pm The IO board should have a jumper to set the fan voltage to either 5v or 3,3v.
It´s right next to the fan header.
Could have fallen of/forgot to install during building so check that it´s there.

That was the exact solution in my case.

My 6.1 I/O board came with no jumper caps whatsoever.

I've scavenged a couple from old HDDs and whatnot, so I remedied that particular problem.

Please note, the 'semi-official' Noctua NF-A4x10 5V fan will not run @ 3.3V as advertised, so take care to put the jumper on the 5V setting.

Edited for fake news

lamarax wrote: ↑Sun Nov 22, 2020 8:54 pm Please note, the 'semi-official' Noctua NF-A4x10 5V fan will not run @ 3.3V as advertised, so take care to put the jumper on the 5V setting.

I think your fan is possibly faulty as the Noctua NF-A4x10 5V should work perfectly using the 3.3 volt jumper selection, albeit at a lower rpm.

Nat wrote: ↑Mon Nov 23, 2020 9:54 am I think your fan is possibly faulty as the Noctua NF-A4x10 5V should work perfectly using the 3.3 volt jumper selection, albeit at a lower rpm.

My bad; you're quite right actually! I tested again and the fan does indeed run @3.3V.

The quietness + the "rotoscope" kind of illusion under the enclosure's grille had me fooled