The classic Mac Pro has always intrigued me in some way. There is something about the whole concept and design that really attracts me. From the outside, now more than 10 years after the release of it, it still looks nice and up to date. Everything about it tells you that this is a powerful machine. Internally, the design is different from what is considered standard but it works very well. Although Apple did their best to restrict this, after performing some minimal and relatively cheap upgrades to a Mac Pro 4,1, it is still more than usable in 2021. In this post I will go, step by step, through the upgrade process for a cMP 4,1 from both hardware as software perspective, all the way up to a performant Big Sur Mac Pro machine.