Updated Case for Multi-Expansion Board

[Parardroyd]

A resistor will limit the current, not the voltage. So, a resistor will have a limited affect on the speed.  Using a resistor will work up to a point where the fan won't turn on, but will have a minimal affect on the speed difference and that will vary from fan to fan.  Start with a small value, like 100 ohms.  That would reduce the max current to 50mA.

Hmm..maybe it would make more sense to tap into one of the 3.3V supply pins on one of the GPIOs then instead. I could probably just do that instead of plugging into the designated 5V socket (assuming it IS 5V, I haven't measured yet) on the expansion board that it's normally plugged into.

What is the part designation of the connector that the fan uses to connect to the expansion board, if you don't mind?
If I can get one of those, I can just plug the fan into that and route it to one of those 3.3s and not have to cut into anything or make any permanent mods.

Anyway, thanks for the info!

[admin]

3.3V is not enough to run these fans, and it would interject too much noise on the 3.3V line if it would work.  I would recommend a standard diode (1N4001 or similar) in series with either 5V or ground going to the fan (you will need use the proper polarity in order to make it spin).  Standard diodes have about a 0.7V drop.  You might be able to put two in series to drop the voltage by 1.4V.

Personally, I have not used a fan with the DE-10 in 2 years now.  It's not needed.  Future versions of this board will not longer have a fan cutout.  You don't actually need a fan or a heat sink (per Terasic, the manufacturer of the DE-10 Nano).  I did a test where I ran the DE-10 without a heatsink or fan in a setup with an ambient room temperature ranging from 100 to 145 degrees F for several weeks with no issues.

[Parardroyd]

3.3V is not enough to run these fans, and it would interject too much noise on the 3.3V line if it would work.  I would recommend a standard diode (1N4001 or similar) in series with either 5V or ground going to the fan (you will need use the proper polarity in order to make it spin).  Standard diodes have about a 0.7V drop.  You might be able to put two in series to drop the voltage by 1.4V.

Personally, I have not used a fan with the DE-10 in 2 years now.  It's not needed.  Future versions of this board will not longer have a fan cutout.  You don't actually need a fan or a heat sink (per Terasic, the manufacturer of the DE-10 Nano).  I did a test where I ran the DE-10 without a heatsink or fan in a setup with an ambient room temperature ranging from 100 to 145 degrees F for several weeks with no issues.

Good enough..I'll probably just leave the fan unplugged then.

I just remember early-on when anyone reported any instability in a core (and as you know many of them had a lot of that in the beginning) the dev's go-to answers were, "are you running a powered hub?", "do you have a heatsink?", and sometimes, "are you running a fan?". If you answered "No" to any of these, they'd often dismiss you and tell you to come back when you'd done all of these things. That tends to get old, so originally I did all of that to eliminate that situation coming up.

I've had similar discussions with people about Raspberry Pis.

I've always maintained that Pis up to a 3B+ absolutely don't need a fan or even a heatsink unless they're being severely overclocked. I've been running around 80 Pi 3B+ as public library kiosks in sealed cabinets with no fans or heatsinks for about 2 years now and I've never seen any instability. In fact in that situation, a fan is a bad thing, because there's a lot of dust in the cabinets and all it does is blow dust across everything.

I also have a fanless Rasberrry PiB (the original version) up up my garage rafters running relays that open and close the garage doors (the garage has no heat or air conditioning). Here in STL, it literally gets up to 130F up there, and the only time that pi has ever had an issue (just once, I think) was after a weird power company off-on-off-on power incident that freaked a lot of equipment out. I manually power cycled it, and haven't had to mess with it again since.

Don't even get me started on all the myths surrounding SD cards...

Anyway, sorry to go off into the weeds there, but I get what you're saying. I'll just leave the fan unplugged. Thanks, and FWIW, I'll probably be buying another one of these boards for my other DE-10 in a week or two.