<p>My anet A8 stepper drivers get very hot after some time printing, so I decided to install a 5V fan to cool them down. I had the idea to get a 12V to 5V regulator to connect a 5V fan, but then i found this image:</p>

<p><a href="https://i.stack.imgur.com/Ryeyj.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/Ryeyj.jpg" alt="anet a8 mainboard"></a></p>

<p>(source: <a href="http://lokspace.eu/anet-a8-wifi-mod/" rel="noreferrer">lokspace.eu</a>)</p>

<p>It looks like the Anet A8 has an ICSP and Serial header that can deliver 5 or 3.3 V directly from the board. Is this correct? If it is, how many amps can i get from this pin? Can I connect a 5V fan directly here?</p>

<p>Thanks and sorry for my bad English.</p>

5 V and 3.3 V are both
logic "highs"
in computing and measured against GND. If the fan simply has to know the on stance and nothing more, then you could run a fan with the logic 5 V (and probably 3.3 V for about 50% spin speed).