21002Mhz Assuming you mean 2133Mhz or 2666Mhz here

Which Ryzen 3000 Chip, how many memory modules, and how many ranks on each module (single-rank has chips on one side, dual-rank has chips on both sides)?

Memory support is going to vary on those three factors.

Search for your CPU and open AMD’s “Drivers and Downloads” page for that CPU, then expand the “Connectivity” section and scroll to see what your CPU officially supports.

Take, for example, the Ryzen 5 3500G: https://www.amd.com/en/support/downloads/drivers.html/processors/ryzen/ryzen-3000-series/amd-ryzen-5-3400g.html

Max Memory Speed

2x1R DDR4-2933

2x2R DDR4-2667

4x1R DDR4-2133

4x2R DDR4-1866

Most CPU samples can run faster than what’s listed there, but it’s not a given.

In any case, I recommend running 4-8 passes of Memtest86 to make sure a memory configuration is stable. That becomes especially important when running “out of spec”.

Memtest86 can also be used to validate whether or not your memory (or CPU memory controller) is defective. Statistically speaking, it’s usually the memory.

If needed, you can enable XMP and then go under advanced settings and manually set a a specific memory frequency.

Please note that the lack of BSODs does not necessarily indicate actual stability. I’ve diagnosed plenty of cases where a client’s installation is silently corrupting over the span of months because of an erroneous memory configuration. The only way to know a config is for sure stable is to set a configuration, run Memtest86, and then see 4-8 passes complete without reporting any errors.