Reviewers and GPU aficionados have previously observed that there are two "classes" of the dies that make up NVIDIA RTX cards. They are essentially the TU10x-xxxA and TUx-xxx chips, the "A"s of which are approved for factory overclocking. However, new variants of the same dies negate this dichotomy.
https://www.notebookcheck.net/New-Turing-dies-set-to-put-an-end-to-the-two-tier-system-for-RTX-cards.420122.0.html