I've always liked the look of the MacPro 4/5,1 and decided to buy one in 2022 to satisfy the itch. There's an excellent guide to upgrading a MacPro in the links below which I used as my getting started guide. Owning an old computer of any type is like owning a classic car, lots of trouble and almost always outperformed by the newer model. A 5,1 however will perform the function of workhorse better than any other Mac I've owned and will mostly be used for folding routines-I have access to free power.
On 10/17/2022, I purchased an Apple Mac Pro 5,1 12 Core 2x 3.46 GHz Intel Xeon 128GB RAM Radeon 560 Graphics for $717.04 shipped. Unlike many of the other listings on ebay, this came with max ram and the highest CPU upgrade possible. Where most people used this for video production, the original owner was audio focused so the graphics card was servicable and would be more than enough for my application.
The box arrived and it was much heavier than I expected even knowning that it was a big metal case.
I managed to get Mojave working through the OpenCore Legacy Install utility which is absolutely not supposed to work if you ask Reddit.
I wanted a RAID so I bought a Sonnet 4 slot M2 NVME card and found a great deal (aka retail price) on 4 Samsung 970 Pro 1TB drives. The installation required a driver from Sonnet. I also purchased (but haven't installed) a pre-flashed Thunderbolt card in case I want to connect it to my existing eGPU in the future. I also removed a stick of memory from each bank in the system leaving 2 slots empt because the Intel chips are 3 channel and I opted for a slight speed increase over memory. Finally, I added an upgraded USB card and a 2x 10GBe card to the system. The display is an old metal case studio display which I purchased as new old stock. It's lovely.
There are a variety of challenges that Apple creates: