You should look for a minimum of 4-5VMs with 16-32GB of RAM. Else, you can opt for a minimum of 8GB of RAM. Moreover, your chosen laptop must run Kali on a VM for enhanced cybersecurity.
Always go for a laptop with a six-core or late quad-core. Any quad-core processor can assist in data crunching or password cracking. However, it’s not still necessary to opt for quad-core, and you can go for any other preferred processor.
Are you looking for an accelerated brute force password cracking process? You should opt for the latest NVIDIA GPUs. How many VRAM & CUDA cores would be there on your laptop will depend upon your budget.