It seems that you went from a desktop PC to a notebook. Your "new" i9 processor is actually about 20% slower than your "older" i7 if you want to believe UserBenchmark.
There are multiple reasons for this:
- As @Rik pointed out, you went back a CPU Generation
- The H-processors are notebook CPUs and draw way less power than a desktop CPU and are therefore slower
The following reasons can contribute but don't necessarily have to:
- Not enough cooling on the notebook
- Notebook not set to best performance (in Windows)
- Notebook not connected to a charger
I understand your confusion though. Customers just look at the front of the processor name (i5, i7, i9) and think a higher number would result in better performance. Which should be like this, but is not. The generation is very important and notbook CPUs and GPUs are always slower than their desktop equivalent.
But you're in luck since intel H-CPUs are the fastest notebook CPUs (from intel). U-CPUs are the slowest and P-CPUs are a midpoint. This is done, because 'slower' also means better battery life.