You don't really need an upgrade in anything.
The common mistake of beginners, that they think, having a bigger/larger/stronger computer is a requirement for doing things uncommon for ordinary computer users. It is not.
I type this answer for you on a 2006 macbook running a 32-bit Linux. Although for development, I use mostly servers (these are strong) and laptops (these are roughly like yours).
Not that is important, how strong is your computer, what is important, what do you develop on it.
Furthermore, you have a strong laptop. It can't be really upgraded, because
- Laptops are not really modular (far lesser of its parts are changeable)
- it is already close to the top. You will need to invest a lot to get only a little improvement.
We can formalize your specification so:
- You have the laptop specified in your question
- You have \$4k
- This is what you convert to the possible strongest laptop (for AI development).
Then the answer is this: buy the costliest laptop from $4k and you will end up with two laptops. But you don't need this second laptop.
Today, AI development means most likely by using the video card as a massively parallel CPU, thus this $4k laptop would likely need a strong GPU, if you would really need it.
- Learn languages (python, C++, what you have).
- Please, please, please try in your life once an OS what is not windows. It does not matter, what. The important thing is to understand, what an OS is doing, and that it is not only a GUI.
- If you have some academic connection, learn Latex.
- Refresh your Math and algorithm theory.
You need these. Use a part of the $4k to buy AI books in the university book store (or rent them from the internet). Most internet sources are still nowhere to the quality of the paper books in an university book store (library). The current world works so, that you can learn a lot from the Internet - the difference between a graduate and an internet programmer is what can't be.