before you go replacing the fan with a different model you might want to check the power the current fan uses and how many watts the replacement uses. if the replacement uses too much ur gonna damage the controller. it may work for a bit of time but the extra wear on components will take its toll eventually and they will fail. are you willing to take that chance? that fan you posted uses almost 40 watts of power....im not sure what the stock fan is rated at.
The actual model of the fan is 'Delta QFR1212GHE" Its DC12v @ 2.70Ampere. This is the PUSH fan. located in front with your LAN cable. I have a broken S9 that's why I saw it's model inside.
Isn't it better to use a bigger Ampere fan so that its lifetime is stretched longer? I mean the controller gives the same volt and amp when powering the fan, meaning the 3amp fan can handle a full power from the controller and still has extra .30ampere (3amp minus 2.70amp). Am I right? I also want to confirm this... Anyone with electronics knowledge please. I want to buy a aluminum framed 12v 4amp fan it will really look bad ass. If i can use it..
Here is my fan FAN DATASHEET
Normally a consumer "pulls" the amount of current it "needs" (given its internal resistance), though there are exceptions, where a supply will only "give" a max current (usually by changing the voltage). V=IR (for a supply V is usually fixed and the R is given by the applyance, then I is derived from the combo).
these are PWM fans so the voltage will stay the same at 12v plus or minus 10%. 3 pin fans are controlled via the voltage being pushed to the fan. if the controller can handle 3a max that doesn't mean its using 3a all the time. the usage depends on the fans speed and how efficient that fan is at moving the high volume of air through the limited and restricted space...basically like the guy above said the static pressure. pushing air through a hollow tube is much easier than pushing it through a tube with obstructions which is what the s9 is. You should also note that just because the fan spins faster or has a higher CFM doesnt mean its a better fan. it can use more power due to an inefficient design and also if the fan isnt designed for a high static pressure it can move all the air in the world and it still wouldnt be able to work with the s9's design. So there is alot more to fan swap outs than just voltage amperage and cfm.
NotFuzzyWarm - yessir...i dont think the tiny traces can handle much more power than they are handling now but honestly i wouldnt want to test it anyway. chances are the traces are just the right size for the fans being used now and since mining is a numbers game im positive bitmain is trying to cut costs wherever possible even if that means making traces less able to handle bigger loads. smaller traces + less material = some savings that add up based on the number of boards they have produced. you can do what you mentioned and unhook the red and black wire and power them on directly from the 12v supply. You can also control the fan speed of ann the s9's if you unhook the blue wire and connect that to an external pwm controller. it has to be a 4 pin controller though not a 3 pin and it can only be the blue wire...the other wires stay in the molex connected to the controller. I posted this info in a previous post but if you think its a good idea so you can run the miner in your living room think again....it raises the temps so you need super cooling to run them at lower speeds and on new models you cant control the freq at all so its really only usable on pre auto tune firmware unless you have beastly cooling setup.
