Need help troubleshooting a ryzen 1800x PC build for a friend. Laggy BIOS, Black screens etc

[ghostXI]

I am currently building a gaming/streaming/mining PC for a friend and am having issues getting everything going. I am new to the Ryzen platform and have always worked on/built intel PC's in the past so I am less familiar with them. The issues specifically are the bios lagging, super slow mouse movements while in it. Long time on the splash screen on start up. Sometimes PC does not appear to post, hangs on black screen.

Here are the parts:
-R7 1800x at stock with H120 water cooler
-ASUS Strix B350F Motherboard
-MSI GTX 1060 6GB Armor
-Corsair LPX 8GB 2400mhz (1 stick) CMK16GX4M2A2400C16
-EVGA Supernova 850w PSU
-Sandisk 120gb SSD

I have the whole system on a test bench, have since disconnected the SSD and tried out different ram to troubleshoot etc.

Things I have done so far:
-Tried new power supply, tested in known working system...works fine
-Tried new ram, tested in known working system...works fine
-Tried new GPU, tested in known working system...works fine
-Update BIOS to latest version
-Tried changing ram frequency, same results
-Kept settings on optimized defaults on the motherboard

More backstory. We initially thought it was the motherboard causing the issue after trying every other component in different configs...so he got a new motherboard the ASUS strix 5350-F. Previous motherboard was having the same issues as this one (gigabyte B350) Also temps are showing 37c in bios.

Whew. Sorry for the overload, just want to get this fixed up for him and wanted to see if anyone could point me in the right direction. Thanks so much!

 

[ghostXI]

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