Ryzen 3600 - 4.35GHz @ 1.225v - Newbie Overclock Q's & Prime95 Stress Q's
So first off let me list out my spec and then go into my results/tests/questions, btw its been 15 years since I last had/overclocked a PC at a kid so be kind.
Ryzen 3600 - 4.35GHZ @ 1.225v - Infinity Fabric @ 1800
Cryorg H7 Aircooler - Base has been lapped flat as these are very convex so not suited to the Ryzen 3000 chip layout (this yielded a massive reduction in temps when this was done, as it was reaching 90C when completely stock)
Asrock B450m Pro 4 - Bios 3.90
16 GB Corsair Vengence 3600 CL18 - Stock Timings/XMP Profile
WD Blue SN550 M.2 Pcie Nvme - 500GB
Sapphire Radeon RX5600XT
Windows 10 Pro + all latest updates/drivers etc
So I'm currently just using Ryzen Master so I could do incremental OC's without having to reboot etc to find something stable/fast etc
I reached a seemingly stable 4.35GHz @ 1.225v @ 30-34C idle and was able to run the entire Blender suite of benchmarks (about 30ish mins long) and also Cinebench r20 on loop for 30 mins without any stability issues at all and temperatures reaching 75C but held stable there.
Though after these benchmarks I decided to run Prime95 Small FFT test and this crashed/shutdown the computer after only about 10-30 seconds even though temperatures weren't super crazy but at mid to high 80's C. I found it odd as I ran the Blender benchmarks and the Cinebench for decent periods of time without any issues at all and with decent temperatures with zero crashed.
So I went about playing with the overclock and voltages until I was able to successfully run Prime95 Small FFT test for 30mins without any issues @ a constant 82C with 4.25GHz @ 1.1875v
So my questions:
Why is my original overclock seemingly stable in any real world benchmarks yet Prime 95 Small FFT test instantly causing it to crash almost instantly? Is this test a that I should always run to ensure a stable overclock?
I noticed stock when using PBO in Ryzen Master I was generally getting 4GHz all core and 4.19Ghz singled threaded stuff. But I noticed my Core Voltage would shoot around loads more under idle fluctuating temps and under load often going way higher (1.4v+) yet on getting around 4GHz all core so temperatures were actually higher with considerable high temperatures to my overclock setup, is this normal ?