Yes, it's safe to connect a 2-pin fan to a Mobo.
Yes, it's safe to connect a 2-pin fan to a Mobo.
I replaced the fan with a standard connector but noticed missing parts like ground, power, PWM, and yellow wire. I'm unsure if it's safe to connect it to the motherboard or if using a PSU is better.
It suggests using two pins to keep the fan spinning at maximum speed continuously. Omitting the third pin means it won’t show speed readings. Skipping the fourth pin removes PWM speed adjustment. It’s not a big issue as long as you’re okay with the fan running at full power for the duration.
Thanks for the concern, but don't worry about the fan drawing extra current from your old Dell motherboard.