PWM 3-Pin Adapter:
I wasn't sure it was possible until I did it. I have an adequate understanding of electronics in theory, but I don't often get to make myself real circuits. I knew though, that transistors act as switches when used properly. I used that and developed the idea in my head, and then I made use of my rudimentary google-fu and came across this post.
"Perfect," I thought, "I wasn't the only one to have the idea!"
And so I pushed forward after a couple days debating between building what the original poster's question suggested and the more robust solution provided in an answer given. I used what components I had on hand, an intermediate resistor and a 2222A transistor, and assembled as above - also as a schematic here (image found on the post):
I don't have much in the way of RPM data at different PWM levels (probably need to re-crimp that wire), but I did manage to go from ~2311 RPM at 100% PWM, to ~760 RPM at 80%, according to the ASRock Tuning software. I was using a low noise adapter also.
