pls help, new seasonic m12IIbronze won't start up...

Hi all,

I have an HTPC with intel core i3-2100/gigabyte h67ma-d2h-b3 mobo, which i've been powering with an antec true power 650 for the past 6 months, no problems.

i'm building another computer for work/moderate gaming, and i was planning to use the antec power supply (which is pretty cramped in my moncaso 312 case), for a modular seasonic m2IIbronze 520W.

so i install the seasonic, hook two cables each with 3x sata, attach the 24 pin mobo connector, and attach one of the 2 4-pin 12v connectors to the mobo.....nothing happens when i push the power button....

am i doing something wrong here? is the 4/8 12V connector not compatible with my mobo??? i feel like that doesn't make any sense. the antec had a 4-pin 12V by itself, and that worked fine.....

please help!

Hmm...only one of the 4-pin should fit anyways, so you must have the right one plugged in. Now, for the possibly dumb, but necessary questions...

Do you have the switch flipped on the back of the PSU?
Is your front panel power switch plugged into the motherboard?
Is the PSU plugged into the wall?
Are the connections secure?