archaic0

A while back I purchased an M2-ATX from the store here and had some problems with it. It powered my system fine, it simply would not turn it on and off reliably.

I spent a while in the forums with people and their conclusion was that my rig was too powerful for the 160W psu but this seemed a stretch for me. I bought an OPUS 320 though to see if that cleared up the problem.

The OPUS acted the same way upon initial install. If I left the power switch under my manual control then the psu provided power just fine. I just couldn't get the psu to turn my machine on and off.

On a whim I thought I remembered seeing some kind of power switch mode option in the manual so I looked and found the AT operation setting. That worked and continues to work like a champ.

I didn't go back to look and see if the option exists on the M2-ATX because I just figured I would stick with the bigger one.

Anybody know why this might have happened? Why do I have to put the psu in AT mode when it's an ATX motherboard?

SenatorIvy

The J10 jumper setting on the M2ATX adjusts the powerscheme, if I follow what you're saying here.

I believe leaving the jumpers all open would yield the same result as what you did with the Opus.

archaic0

Well I'll try the M2 again with that and see if it works well. If so, I may switch back to the M2 and sell the opus. I'm fairly sure that I don't need a PSU that big now.

wrbrower

For ATX mobos there are usually two settings that can be applied to the front panel power button (thus M2-ATX).

Instant Off: Allows power off immediately upon pressing the power button. The operating system will begin an orderly shutdown as not to corrupt Windows.

Delay 4 sec: the system powers off when the power button is pressed for more than four seconds or enters the suspend mode when pressed for less than four seconds.