I really do think Ryzen overclocking is sensitive to temps. I spent a lot of time trying to get my 2700X stable at 4.2ghz on my MSI X470 Pro Carbon. I noticed that at 1.425V, it would pass Cinebench runs all day long, but only if I let the CPU cool in between runs. I believe it was around 68 to 70 degrees is where it would crash.
Finally, out of frustration, I just gave up trying to get it stable, as it required more voltage than I was comfortable with. I simply undervolted it, enabled PBO and just let it do it's thing.
I'm on a Corsair H60 with push pull fans at max speed, which does just fine for gaming loads, but not ideal for overclocking. Maybe one day if I get a better cooler I will try again to see if I can get a stable 4.2ghz.
MSI X470 Gaming Pro Carbon
16GB ADATA XPG Z1 DDR4 3000mhz @ 3466mhz
Thermaltake Grand Toughpower RGB 750W GOLD
Nvidia 860M 2GB+BlindRageVbios+335Core+650Memory
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