Two dead Antec power supplies?

I'm building my second system, which I'm installing in an Antec SX830 case with the PP-303-XP power supply. I turn the power on, and absolutely nothing happens--the power supply fan doesn't come on, nor does anything else. I tested the various DC pigtails, and none of them show any power. I'm getting electricity into through the power cord, just apparently not through the power supply.

Even more frustrating, I got a replacement case and power supply, with exactly the same results.

At the risk of sounding like a moron, have I gotten two defective power supplies in a row here, or what might I be doing wrong? Thanks in advance.

Its likely your components are OK. Mobo may have features such as remote turn on, etc that may not be compatible with your power supply or you need to change jumpers. Read carefully the Mobo manual regarding power up options. Some power supplies may not turn on until their sense circuit is completed via the Mobo

regards - Steve