Fortron 350 +12v fluctuations

[Tismedt]

I bought a fortron FSP350-60PN recently and just got it hooked up last night. Everything seems to be working ok but after about two hrs of installing proggies I started to hear my CPU fan randomly bog down for a split second. I loaded MBM5 and started a log. Everything looks good except the +12v rail fluctuates from 12.04 as a high to 11.73. 99.5% of the readings are at 11.98 or 11.92 And I havent started any heavy load testing yet.

Should I pull this PSU and send it back? I scared the hell out of me when I heard the tornado bog down. The other rails are rock solid at 5.05v and 3.3v with no fluctuations at all. This is a new build and I don't have a bunch of stuff installed in this rig Yet. Here's what it has right now

abit nf7-s, 2800 batron, slk-900a w/ a 80mm tornado, 512 pc3200, radeon 8500 (for now), cdr, cd, nexus multi (controlling the tornado) 2 case 80mm case fans.

[squads]

my 12v rail is around 12.92 idle generally and it drops to around 11.8 when i run prime. it doesnt seem to create any problems though. (6 case fans and a volcano 7+) 11.73 is still even within 3% so its ok.

[Tmod]

Sounds as though the PSU is to small for the task at hand.

When the fans slow down during high cpu tasks you need to upgrade.

You should have bought at least the 400.

[larrymoencurly]

Could it be that the load on the +12V rail varies a lot more than those on the +3.3V and +5.0V? If your mobo has the square 4-pin power connector, the +5.0V probably puts out just 15W and the +3.3V just 40W. What kind of variations did you measure with your clamp-on Hall effect ammeter (every Swiss Army knife has one)?

Apparently even a 2% change in voltage can be heard in a change of fan speed. Nonetheless, when in doubt, it's always best to panic and down a bottle of Oxycontin.

[Tismedt]

I havent measured with the multimeter yet but I will after I do a little movie watching with the wife and kids. As for buying a 400 watt I dont think that is the case at all. I'm not running anything outof the ordinary and I havent done any stress tests yet. I think somethings wrong with this PSU

[Tismedt]

Well I just ran a few benchies with my trusty little craftsmen multi plugged in the 12v rail was solid as a rock at 12.05. Go figure. I havent heard the fan bog down since last night so maybe it just needed to settle in abit. I'll still keep an eye on it for the next couple weeks just in case.