I recently got a 5V laptop cooler fan, but when I plug it into a USB port, it doesn't run steadily—it has this weird pulsing effect. I did discard the RPM control cable, so I'm not sure if that impacts it. What's going on?
2 Answers
Sounds like your USB port might be struggling to provide enough power. USB 2.0 and 3.0 should give a steady 5V, but sometimes the current can be too low for the fan, especially if it requires more than 500mA. You might want to try plugging it into a phone charger instead of your laptop's USB.
I had the same problem with a cheap cable before! Try a different one to see if that helps.
Yeah, it sounds like the fan might be drawing too much current for what the USB can handle. It could also be the cable itself—even a poor connection can cause that pulsing. A good idea is to test the fan with a different USB power source to narrow down the issue.
Is it possible that the control cable you tossed out was necessary? Just curious.
Good point! I would definitely try using a different USB cable or a power source and see if the issue persists.

What if it’s the cable? I’ve had issues before with a bad cable causing similar problems.