That video shows the usual. That is, what happens when a new building their first PC. The new builder puts all the parts into the case and this happens.
The cause is usually they shorted out the motherboard with some extra mounting post but in this case we get our cardboard on a work table and forget the case. We put the bare min parts on the table and see if that works before putting it into the case.
Hi,
My configuration is :
EVGA GeForce GTX 1050 Ti
AMD Ryzen 5 1600 Processor with Wraith Spire Cooler
Samsung 960 EVO Series - 250GB
VENGEANC LPX 16GB (2 x 8GB) DDR42400MHz
ASRock AB350 PRO4 ATX Motherboard
EVGA 500W 80 PLUS
So when I turn it on, the computer starts, the monitor remains black, no access to the BIOS, the CPU fan kind of starts then stops (see video), the computer case fan and the video card fan turn normally, the leds of the pc turn on, there is no beep sound (even though I have plugged the system speaker), mobo's leds do not turn on.
I have tried everything said here :
http://www.tomshardware.com/forum/261145-31-perform-steps-posting-post-boot-video-problems
I have placed the RAM on A2 and B2.
See the video:
So I don't know what to do at that point, all the parts are completely new except the motherboard bought on amazon used like new.
Any help please ?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic