One of the reasons working with open source databases such as PostgreSQL can be so effective is that every dollar you save on software licensing can be put toward better hardware instead. The three main components you'll need to balance in your budget are CPUs, memory, and disks, with the disk controller as a related and critical part too.
Balancing hardware spending
CPUs
Currently, available processors are bundling at least 2, and possibly as many as 22, cores into each CPU, making the core count the figure of merit for most database applications and, with PostgreSQL 10.x, we can use multiple cores for every single query with the mechanism called parallel query.
There are two basic decisions you need to make while deciding...