Power problem on new build

Hello all,
New member so, first off, thanks for the forum. It's helped me a lot so far.



Here's my situation: doing my second ever build. I have gotten to power installed (Silverstone 700 watt strider series) in my Antec Solo case, Gigabyte EP45-E3UDR motherboard is in with Intel Core 2 Duo E7300 2.66GHz CPU with 8 GB memory.

All power from PSU hooked up to 24 pin, etc., and all power, reset, fan connectors, etc. from case to MB and from CPU to MB. I want to test power at this point before putting in drives, graphics, etc. So I plugged in the PSU and pressed the power button. I get a brief flash of the power light on the front of the case, then nothing else. No fans, beeps, etc. Nothing. If I unplug the PSU and plug in again, the same thing happens when I press the power button. I have double checked connectors and all seem to be in place with the proper polarity.

BTW, on the Silverstone PSU (ST70) there does not seem to be an I/O switch.

So I know there is some power going through to get the light briefly. Not sure if it's the case, the CPU, the MB or what? Any suggestions, help etc greatly appreciated.

Thanks!
Larry