Hi Barackboy, Yes there is a difference between the 9th Gen i7-9750H and i7-8750H 8th Gen processor. Technically the 9th gen processor has higher clock speed for processing power comparing to the 8th Gen predecessor. While other specs, such as the cache, cores and threads and etc, remains the same. For your reference, the below link is to the difference for both of the processors. Hope this clarifies.

https://www.notebookcheck.net/9750H-vs-8750...6.247596.0.html

In general not much difference (except for i9 which is toasty)