Apprentice Xmas lights question

[Alan Marriott]

Good evening

I’m still learning at college and curious as Xmas just approaching regarding Xmas led string lights and there power supply transformers.

My questions is:

For an example a set of lights we have says 4.5v dc/ 3.6va output.

My question is what happens if:

The voltage output on transformer is higher than rating on Xmas string led lights?

The watts output on transformer is higher than rating on Xmas string led lights?

I’m assuming the more voltage will make them brighter or if it’s too high will cause them to burn out?

As for watts I don’t think that makes a difference as long as output from transformer is higher than load needed?

I could be wrong so can anyone explain for me to learn more.

Thanks