I've already tried the advice for PBO2 Tuning here: https://www.youtube.com/watch?v=-l30dYv4KOo
PBO2 Tuning my 5800X3D (mobo – ASUS ROG Strix X570-F Gaming) had the opposite effect than I expected. BIOS is already set to 142/95/140 and curve optimiser at -30.
My results:
Running the OCCT CPU test the temps settle between 89/90.5deg and OCCT says the CPU is running at 4050ghz to 4100ghz all cores. OCCT says PPT/EDC/TDC usage is 118/81/108.
Running Cinebench R23 then OCCT says CPU freq is locked in at 4300ghz. PPT/EDC/TDC settled around 112/77/121
I used PBO2 tuner to tweak PPT/EDC/TDC to 110/75/105 and ran Cinebench test again. This time CPU clock dropped to 3.9Ghz which is a 400Mhz loss.
I know the 5800X3D is locked in terms of power and temp limits, so you can't really over clock it, but undervolting seems to slow down my CPU. Temps came down as well, but only by about 5deg.
For me the results of undervolting were a small Temp reduction but also a 10% drop is CPU clock speed.
I'm not sure what I need to do differently. My Mobo (ASUS ROG Strix X570-F Gaming) has a load of power settings I can mess with but I'm pretty sure I've got mine set to something reasonable.
I have a Dark Rock Pro 4 cooler, which is supposed to be good enough. (I've tried fresh Thermal paste and made sure it is fitted correctly). Maybe I should grab an AIO water cooler?