robi3, the best results will depend on the speed of your NVMe SSD, and you cannot and should not go by the speed ratings on the box or the manufacturer’s web site.
The speed ratings are for the SSD’s cache. Almost all SSDs have cache, that can range from 25 GB to over 100GB. And the cache is what is super fast. Chia will quickly consume the cache, and then your SSD will run at its native speed, which could be slower than a mechanical hard drive.
There are 4 types of SSD NANDs. From fastest to slowest:
SLC, MLC, TLC, QLC.
The “S” stands for single.
The “M” stands for multiple (as in 2).
The “T” stands for triple.
The “Q” stands for quadruple.
I do not know what the “L” stands for. I believe the “C” stands for “cells”.
Most consumer SSDs are TLC and QLC (probably most are QLC – they cost less to manufacture).
The reason that all are very fast, as long as their cache does not get full, is because their cache is made of the more expensive SLC or MLC NANDs.
There are high-end SSDs, and data center and enterprise level SSDs, where 100% of the SSD is made from SLC or MLC NANDs (and you will pay more for those SSDs).
The SLC and MLC SSDs will not slow down. Chia can hammer away on them relentlessly, and they will perform at full speed 100% of the time.
It is hard to find out which fabric is used with SSDs. But for sure, if it is a TLC or QLC SSD, then it will be bad for Chia plotting.
There is a reason why one 2TB SSD costs $250, and another 2TB SSD costs $450.
And by the way, the SLC SSDs will last the longest, followed by MLC, TLC, and QLC.