DRAM and iGPU Overclocking
Most motherboard vendors have decided to call AMD's advanced CPU features the same thing. So AMD's Cool'n'Quiet can be disabled if you want to disable the CPU's low-power c-states and you can disable C6 as well if you want. Most of the time overclocking the CPU core and setting Windows to high-performance power plan will run your CPU 100% frequency.
Memory overclocking can be done through Ryzen Master by setting memory speed (at half speed, so 1600Mhz is 3200Mhz) and setting timings. You can do the same thing in the UEFI, but you are better off enabling XMP, D.O.C.P, or A-XMP depending on the UEFI vendor. I would only set timings and frequency manually if you decide to go higher in speed or lower in latency than what is listed on your memory stick's sticker, or if the profiles don't work.
Memory voltage can also be set manually if you like or if you are having problems with a profile. Mem VDDIO is equivalent to DRAM voltage, so base should be 1.2v, and most people will set it to 1.35v when overclocking. Mem VTT should be set at half of Mem VDDIO, but most of the time you won't need to set this as it should automatically be half. Remember that SoC voltage helps with memory overclocking too.
You can change GFX (iGPU) clock through Ryzen Master, and you will find GFX Voltage right beside it. I would set the voltage to 1.2v and set your SoC voltage to 1.2v as well; you should sync them when possible. I would start at 1450-1500MHz overclock and move up and down from there.
It isn't too hard to overclock the iGPU; it's about as hard as overclocking a dGPU but with more straight forward settings. On some motherboards, you must set GPU frequency in the UEFI before voltage shows up, and on others, you must set GPU voltage to get frequency overclocks to stick.
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