Legacy Area 51 R1(2010) Cooler Swap PWM pin out question

Hello everyone,

I've searched thoroughly between here and the dell forums seeking out information on doing a cooler swap on an Area-51 R1 desktop. From what I gather you can mod a cable to the Dell powerboard that Command Center uses to retain it's functionality. There were several articles about creating a cable for the 3 pin PWM standard that many CPU coolers use. However, it is only mentioned that this will work for 3 pin coolers. I am specifically looking at an Arctic Liquid Freezer II to put in this case which has a 4 pin PWM. Refer to the attached picture. If I create a cable like referenced in the picture, will the Pulse Width Modulation be active for the cooler?

Dell 5 pin to 4 pin PWM.jpg
 

Cass-Olé

Member
Jan 9, 2013
267
83
Virginia
I probed the top left powerboard & made the below diagram for myself w/my own notes (& own understanding) of what went where. CPU Pump pin4 (should otherwise correspond to a PWM) is in the powerboard 20pin on pin18 & has a red wire that travels down to the MIO board's 24pin (also red) also as pin18. I can't confirm the MIO board spits out a PWM signal however, I havent tested it; you're welcome to google about how to read a PWM signal & from there probe pin4 (of the pump connector 5pin) or probe pin17 red (of the 20pin), if it's active then my guess is the MIO may have been designed to spit out a PWM signal over that pin4

In my photo above u posted of the CB-PWM-D5 (4Pin PWM to Dell 5Pin Converter Black Sleeved Cable, 8inch), that particular would be fine to pass on a PWM signal to cooler motor from MIO (should a PWM signal come from it that is)

I suspect the Arctic cooler can run off of a basic 3pin fan header, meaning it might have a default speed that can work the motor when a PWM signal is absent, contacting them in email or twitter etc might get an answer. It's also probable the motor will run full speed if all it gets is 12Volts/Ground, as would happen with any typical unshielded 3pin-to-Molex adaptor

I do make the Mind-Meld adaptors still, if you're in the US, message me, $12.50/mailed each

A51 PwrBoard  Test.jpg
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s-l1600a.jpg
s-l1600.jpg

51 MM.JPG
 
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Cass-Olé

Member
Jan 9, 2013
267
83
Virginia
Below is a hand-made Mind-Meld cooling adaptor, setup for a 4pin PWM CPU liquid cooling pump motor; hopefully MIO sends out a PWM signal & all is well
PTDC0004b.jpg
If not, I've designed a backdoor in order to grab a PWM signal from one of the mthrbrd fan headers …
Untitled.jpg
PTDC0004a.jpg
In otherwords, using the above single-wire cable, in about 10seconds or less you can back pin4 out of the Mind-Meld's 5pin - now click pin4 into the 2pin female above - that will then connect to the 2pin male which has a 4pin PWM fan connector-end on it that will plug into a mthrbrd 4pin PWM fan header … yes, the above cable can jump into the Mind-Meld (on pin40 & grab a PWM signal from the mthrbrd & direct it back to the pump (if it seems tough to visualize, maybe we'll get an installation photo after it's delivered)

The idea is, hopefully the MIO spits out a PWM signal & the Mind-Meld is all that's needed - BUT IF NOT - the additional wire/cable I made as a backdoor towards grabbing a PWM signal from a mthrbrd fan header can still make the cooler swap a success

Below is another idea I had, so long as you have the necessary parts (4pin PWM Y-Split Cable, Molex SL 5pin connector, SL terminal, wire, fan connector + terminal), it's a viable design which sends a ground signal to MIO board so that CmndCntr will report pump = running
s-l1600a.jpgAbove is a 4pin splitter, & the above design is fine for either a 3pin or 4pin (PWM) pump connector-end … however a 3pin fan splitter cable will also be ok to buy for all 3pin pumps (if so, purchase an empty 3pin female fan connector-end)
 
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