I tried tightening my timings manually from the DRAM calculator values using thus guide: https://github.com/integralfx/MemTestHelper/blob/master/DDR4 OC Guide.md and found my performance dropped or I hit stability issues in Memtest86. It seems the calculator values are really well worked out. I didn't want to try 1.45V as my case is tiny with little airflow over the RAM. I am basically at 3600mhz CL14-17-17-34 at 1.4V on my Dual rank Micron E-die which is only slightly faster in benchmarks than the XMP values despite those being CL16-18-18-38 at 1.37V. The latency is better though at 60ms compared to 70ms. I was hoping for more but I think it is rather that my XMP profile with the X570 Tomahawk and these chips is really good so manual / calculator timings don't have much room for improvement. I tried the calculator values for 3800mhz but it only suggested CL16 which would give worse latency and I doubt the CPU gains would be significant based on HW Unboxed benchmarks comparing 3600 and 3800mhz. I am giving up on further memory tuning at this point but am relatively content with the results. On a separate note, trying to run AutoOC on the CPU or using PBO (I have a 5800X) was really disappointing: neither gave more than a 1% boost in games or 3D Mark and just increased voltage and temperatures. I think the Clock Tuner for Ryzen (also by 1usmus) will be worth doing as it lowers voltages and customises speeds per core but it currently does not support Ryzen 5000 CPUs. I will be running this once the next version releases in the first half of 2021.