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 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.