Connecting fan to mobo or psu

[Spiderbait375]

Is there any difference in fan performance when connecting it to the PSU with molex compared to connecting to the motherboard?

 

[Dashman9000]

Connecting to the PSU via molex will cause the fan to run at 100% all of the time. Connected to the motherboard you have fan / heat curves to adjust the rpm's. No problem connecting to the PSU, just beware it will run full speed and be quite noisy.