PC doesn't run after successful post.

[hanoostreet]

When I turn on my new build pc, after a successful POST, the fans go full speed and after around 30 seconds, they all turn off. I can hear the HDD spinning too. I've unplugged everything multiple times and it still does no work. Nothing shows on monitor and everything is plugged in. Before this, it would go past POST and then make 5 short beeps but I unplugged everything and now I have This problem. I'm using a a320m-hdv and a ryzen 5 2400g. Thanks in advance.

 

[RaidHobbit]

Beeping indicates something isn't plugged in correctly.

 

[Obakasama]

In addition to what RaidHobbit states, there's also the possibility the motherboard hasn't got the BIOS to support the 2400G. Hopefully you've come across the POST sticky: http://www.tomshardware.co.uk/forum/261145-31-perform-steps-posting-post-boot-video-problems

If no joy from that then I suspect it's the BIOS. In which case you should look to get a boot kit: https://support.amd.com/en-us/kb-articles/Pages/2Gen-Ryzen-AM4-System-Bootup.aspx