12V on psu

I hooked up a cold cathode to my backup psu to test it out, and noticed it was flickering. So I took out my multimeter to measure the 12V on the psu, and noticed that the psu would move from 11.6V to 12.2V every 10 seconds or so. I took out my new antec 400W, and it stayed at 12V or so consistently. When I used to test my rheostat baybus, I remember the led blinking like the cold cathode was, and am thinking because of my screwy psu. Is this just a junk psu or did something happen to it?

If you're certain that the Rheobus or the cold cathode aren't putting a wavering load on the 12v rail, the PS is not acceptable. Kinda doesn't matter if something happened to it, or the PS is of poor quality.

Matt, you say it was a backup PSU. Did you have anything else hooked up to it? For the +12V o/p to stabilize, you need a nominal load on the +5V output.

Hoot

No, nothing was on the 5V rail. That would make sense, I just use this psu to test stuff or if I need it to backup another psu that might die in my systems.

Get a 5 ohm 10W power resistor and hang it on one of the +5V outputs and a return (black) wire. That should settle it down. It may be low, but not jumping around as much.

Hoot