Do UC's look at capped weighted GPA or fully weighted GPA?

I am confused on why there is a 8 class limitation for honors and ap classes when trying to calculate your weighted GPA. What is the difference between capped weighted GPA versus fully weighted GPA?

All UC’s use the capped weighted but UCLA/UCB will also use the fully weighted (unlimited Honors points for a-g courses that meet the criteria taken 10-11th grades).

https://rogerhub.com/gpa-calculator-uc/

they see your full transcript and consider course rigor. I’ve read their rationale is twofold. - first some schools only offer a few APs so, it mitigates the advantage of attending a school with dozens. Second, most kids can’t handle the workload of more than 2 APs a year so, they discourage people from signing up for 5 and killing themselves.