swap what pins??

i dont think swapping the fan pins will have the effect im looking for.

Sorry for my paint skills but i think i need to make this for my fan to work correctly.. any electrical engineers in here to check my work?



not sure if that L7805 will get too hot..

also im not sure what the value of R2 should be.. or maybe it doesnt matter? the higher level of R2 the slower the fan will run, i think?

the transistor is 2n2222 or something? NPN i think?

I tried running the pull fan on a problem S3 at full speed and found that to get it done and still have speed readings I had to cut the blue wire and bring that from the fan to the supply 12v while leaving the hashboard blue wire dead ended.  

I bought a PWM speed controller from China and was going to put the output to the blue wire and have an adjustable fan speed control with normal speed feedback to the GUI.  But, since I wanted to troubleshoot the problem S3 I put it back to stock and haven't attempted the variable speed yet.  I decided I wanted to get some connectors so as not to cut the wires as the fans don't have a lot of extra lead length.  Also, summer is on its way and I may just want full speed on fans so then I might be better off with a simple SPDT toggle on each fan for hashboard dictated speed or full speed.

I wonder why on the S3's there are two different fan speeds.  When I added a pull fan to my S5 I took its power from the 12v supply without concern for variable speed.  The fan cable splitters on ebay would seem good for adding a fan to an S5, again why two fan speeds.  And on an S3 the splitter could be put to the board with faster fan and then have a SPST toggling the fans' blue wire from either the hashboard blue wire output or to supply 12v.  Think I'll order some now, give it a try and then if I'm happy with the option I'll put it on all my miners for the summer.  Though mid-summer I may be shutting down during the day and only running at night, remains to be seen.

one of my hashboard has failed once again, sent for RMA.

this is the status for the other hashboard. is the HW error too high?

the hwe does seem a little high for only 15 minutes.. but it might settle down after a few hours of running.. id check it over night.

also that fan is spinning way too slow.. is it the stock fan?? should be 3500 rpms at that temp..


what power supply are you using?

There are voltage regulators that will accept 12V input, and deliver a variable voltage output, controlled by a potentiometer on the board. They will handle 10's of Watts, and cost $10-15 on Amazon or Ebay. For many people this will be way easier, and less expensive, that trying to build one.

What's wrong with the stock fan?

nothing is wrong with the stock fan, i bought another fan like it to run in pull, but it ended up being pwm inverted.. i fixed it up tho and my temps are good..
and its alot quieter with 2 fans running at half the speed.

unfortunately the S5 doesn't have the balanced option that the s3 has..

any particular reason you want to mine 2 places at once?

no but i used UPS..