Ryzen5 2400g system won't post or boot

[lilern]

Hello! I just got done putting together my PC.
Components:
Ryzen 5 2400g
Ab350 pro4 Mobo
Corsair vengance 2x8gb 2666mhz
Crucial 250gb SSD.
Coolermaster masterliquid ml240l rgb aio.
Windows 7 64bit
When I click the power button the whole system turns on and runs for about 25 seconds then off for about 3 seconds and repeats over over and over.

I've gone over it all and made sure all is plugged in and plugged in correctly. This is my first build and I need help so any response would be helpful! Thanks!!

 

[Calvin7]

ASRock offers Windows 7 USB Patcher ver:2.0.16 for some CPUs, however the motherboard is listed as supporting only Windows 10.
https://www.asrock.com/MB/AMD/AB350%20Pro4/index.asp#Specification

Look for "Ryzen Desktop 2000 ready" badge on motherboard box. If you don't have that badge, then you can get a "boot kit" from AMD to flash the BIOS.
https://support.amd.com/en-us/kb-articles/Pages/2Gen-Ryzen-AM4-System-Bootup.aspx

 

[maleonardi1]

Op did you ever get this figured out? I'm having the same issue with a similar parts list

 

[mrmojorizen]

I got the same config. I think the other Ryzen CPU's work with WIN7, but the G series seem to be incompatible (due to GPU on chip?). I got a Desktop 2000 ready copy of the Asrock mobo, even updated to 4.7, but get the
Mobo is not fully ACPI compliant message after windows tries to load files. Using ODD & PS2.

Solution is either use Win 10 (rather not) or exchange for non G series Ryzen. If anyone can prove me wrong, please do. I've seen videos of Ryzen running on windows 7, but not the 2400G.