Not overclocked, default clocks.
I am connect with support of Sapphire and it says that 30w at idle its normal for Pulse and Nitro. But they do not explain why?
NO, it's not normal!
RX 5700 (XT) have the same problem (i also with my 75Hz monitor)
The graphics cards are unnecessarily loud and hot!
Meanwhile you can find thousands of threads of this driver bug!
We must hope AMD will fix it finally...