Additional PSU on a miner - 3.3V/5V without load = bad?

[yakavetta]

I was wondering if a PSU which is used for mining that doesn't have a mainboard needs load on the 3.3V/5V  main power plug.

Read something about the coils and or capacitor on 3.3/5V being unable to unload resulting in peaks switching on/off which may damage the PSU. Not to sure what I read there

Please only reply if you know it in theory if it is "ok" to use the PSU without 3.3/5V load or not.
I know it "works" somehow. Want to know it technically.

Thx in advance.