I put an Apple 4x PCIe AHCI SSD, a Radeon R9 280X, 2 additional SATA SSDs, and a USB 3 card into a 2006 Mac Pro with dual quadcores and 32GB RAM. In doing so, I

I put an Apple 4x PCIe AHCI SSD, a Radeon R9 280X, 2 additional SATA SSDs, and a USB 3 card into a 2006 Mac Pro with dual quadcores and 32GB RAM. In doing so, I converted it into a useful computer-cum-space-heater that handles almost any modern workload I can throw at it, except for things requiring AVX extensions that the CPUs don't support. edit: even games! Even moderately-recent ones!