In reply to omer_kafkaos:
What you are describing is not all assigned to scoreboards.
I try to answer your questions:
(1) you need in any case a reference model for comparing output values in verification. The most simple but most risky one is using your brain as the ref model by interpreting the design spec. You should check if you have other kindes of ref models like C/C++ code or even a TL model.
(2) the clock accuracy is not checked by your scoreboard. But you can use other mechanisms like SV assertion. This is a really good application for them.
(3) Of course you can use textfiles with your ref data as your reference model. But this is not a smart and flexible solution.
(4) UVM allows you to connect other tools like Matlab to it and use them as ref model.
Hope this gives you some more insight.