On a piece of cardboard.
Psu + mobo + Cpu/hsf.
Nothing else connected or plugged in.
If it does not power up your down to 3 parts.
Hello. I am building my first gaming pc and as I'm building it i can't get it to go to post. First of all when I flip the switch on the psu it turns on for about 5 sec without pressing the power button and then shuts off. Also, I tried this with the power and reset button unplugged from the mobo and it still happens. As far as I know everything was done correctly and is plugged in. I've even switched out the psu and got the same result. Any help on this would be great!
Specs:
Intel - Pentium G4600 3.6GHz Dual-Core Processor
Gigabyte - GA-B250M-DS3H Micro ATX LGA1151 Motherboard
Corsair - Vengeance LPX 8GB (1 x 8GB) DDR4-2400 Memory
SanDisk - X400 256GB 2.5" Solid State Drive
Gigabyte - GeForce GTX 1050 Ti 4GB G1 Gaming Video Card
EVGA - BQ 600W 80+ Bronze Certified Semi-Modular ATX Power Supply
Asus - DRW-24F1ST DVD/CD Writer
NZXT - Phantom 410 (Red) ATX Mid Tower Case

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic