When the computer is idle in the desktop a power saving feature kicks in which causes the computer to hard freeze

The computer never locks up when gaming or doing other intensive task

Changing these options in the BIOS have given me a solid 4 days of uptime with the majority of that time being idle on the desktop

FIX THAT WORKS FOR ME

Advanced --> CPU configuration --> Cool'n Quiet --> Disabled

Advanced --> AMD CBS --> Zen Common Options --> Power Supply Idle Control --> Typical Current Idle

Advanced --> AMD CBS --> Zen Common Options --> Global C-state control --> Disabled

Here is a thread that talks about it

https://lime-technology.com/forums/topic/61767-amd-ryzen-update/

and

https://bugzilla.kernel.org/show_bug.cgi?id=196683

Here are some ASROCk AB350M Pro4 threads

http://forum.asrock.com/forum_posts.asp?TID=7651&PN=25&title=asrock-ab350m-pro4-freezing

and

https://www.reddit.com/r/Amd/comments/78pc3x/new_pc_amd_ryzen_5_1600_32_asrock_ab350m_pro4/

AB350M Pro4 (on bios P3.40)

AMD A8-9600 (stock and using the INT R7 GPU)

Samsung 961 256GB NVME SSD

16GB Team Group Dark Pro 3200 B-die @2400Mhz (because I want this kit for future Zen 2, or at least a black friday on sale 2700X, later in the year, lol and a new mobo)

I'm on bios 3.40 Bridge of course because it runs the best with BR and SR so far and is the recommended bios for Bristol Ridge and Summit Ridge. Raven Ridge and newer Pinnacle Ridge chips probably need to be on newer BIOS versions.

By the way, my board only has issues if I disable Cool'n'Quiet and start setting voltages. It then reboots or freezes constantly. Running stock BIOS settings it runs day after day without any issue what so ever. I am trying Cool'n'Quiet disabled with no other changes to the BIOS to see if I can at least do that.

Thanks to the OP for this thread.

I can't run the latest 4.xx bios as I am not using Ryzen 2 yet. When I upgraded to 4.xx it was nothing but unstable and felt generally slower. ASRock has been releasing those versions specifically for Ryzen 2 chips.

I am not gaming on this system and have no plans to do so. It has only once hard froze and I was on bios 4.70 when it did. My AB350M was spontaneously rebooting, but as far as I could tell ONLY when I disabled Cool'n'Quiet and started trying setting my own voltages. I could not find a stable setting after disabling Cool'n'Quiet, so I gave up since I really do not need it on this machine. And all I wanted was 3.8Ghz at minimum, lol.

I thought it was temps at first, but my IR temp gun says that's a crock of crap. Using my IR gun I have not seen temps over 41c which should NOT cause any issues. So there's that... I would redo the tim on the chipset and use some fujipoly on the VRM's, but why bother if its stable at stock settings? Its just a ebay biz running machine. At 52 years old I am getting very lazy. lol

I might try again when the next BIOS is released.

EDIT: Thought I might let ya know I was gifted this board by my Uncle who said it froze every 15 minutes of every day but NOT during gaming (so yes to your question). He used a Ryzen 5 1600 on it and I am NOT (hmm). I do not know what his settings were, or if he even bothered changing them. His first reaction to issues like this is buying "other" hardware, lol. So he got a Prime board instead and its been running flawless for him.

Since I got this A8 to update the bios for Ryzen I will have to wait until then. I might be waiting a long time though as I can't afford to upgrade it just yet. Maybe during black friday later this year I hope. I just have too many other money sucking projects here unfortunately.

Its only three settings, so give it a try. Please let us know if you have all three settings and what BIOS you are running, please.

My board is the AB350 Pro4 and the other thread was for the AB350M Pro4

Yeah these two boards which kinda look similar really are not very similar. One has great reviews on Newegg (your non-M variant), and the other (The M variant)... not so much, lol. I guess the M stands for "Meh"

Replaced... with a second unit of the same product, replaced with another model but keeping mATX format of the same brand, replaced with another brand of MB... ???

Ryzen APU's are killing Asrock's MB something. B450's may be just shipping, wonder if they could handle properly.