I have a configuration with 20,000 points. How fast a computer do I need to purchase for this system?

The CPU requirements are a direct function of the dynamics of your system. Sinolta is a highly multi-thread system. While the faster, the better, it is the number of cores that makes a difference.
We recommend using a system with 4 cores (8 logical processors) or better. If you are planning to have intensive data logging and several simultaneous users, we would recommend using more cores. As a general term, the faster the computer, the quicker the system will respond. The other factor that plays an important role is the future growth for this system. You can start small and upgrade your computer later or set up a large server that will be good for the next 10 years.