There are lots of threads for this you just need to use the search bar.

GPU are the most important components of mining, but however choosing the right cpu for your mining rig is also important. When choosing the right cpu for your mining rigs, there some factors you need to consider, What is your budget? If you have a good budget then i suggest use AMD Ryzen Threadripper 1950X. In performance, this is the best mining cpu of my choice as it has 16 core and 32 thread processor and many more features that gives you a huge advantage on mining.And soon if in case you are planning to turn your back out of mining, you still have a good processor rather than buying a cheap processor and worth nothing in the future. But if you have slim budget, i recommend AMD Ryzen 71800X A decent priced with good performance. However if you think my suggestions is not good. You can search other threads there are plenty of threads regarding this topic. As many people are getting involve in crypto currency. Goodluck.