Ryzen problem, wont post

New build.

Asrock ab350 pro 4, bios ver 4.7

Ryzen 5, 2600

Evo potenza ddr4 2x4gb ram

700watt thermaltake psu

Toshiba 1tb hdd.

I usd a spare amd a6 9500 to upgrade bios from 4.6 to 4.7, 4.7 should be compatable with the r5 2600, but even with update, pc won't post.