Mac Pro is a series of workstations and servers for professionals that are designed, developed and marketed by Apple Inc. since 2006. The Mac Pro, by some performance benchmarks, is the most powerful computer that Apple offers. It is one of four desktop computers in the current Mac lineup, sitting above the Mac Mini, iMac and Mac Studio. Introduced in August 2006, the first-generation Mac Pro had two dual-core Xeon Woodcrest processors and a rectangular tower case carried over from the Power Mac G5. It was replaced on April 4, 2007, by a dual quad-core Xeon Clovertown model, then on January 8, 2008, by a dual quad-core Xeon Harpertown model. Revisions in 2010 and 2012 revisions had Nehalem/Westmere architecture Intel Xeon processors. In December 2013, Apple released a new cylindrical Mac Pro (colloquially called the "trash can Mac Pro"). Apple said it offered twice the overall performance of the first generation while taking up less than one-eighth the volume. It had up to a 12-core Xeon E5 processor, dual AMD FirePro D series GPUs, PCIe-based flash storage, and an HDMI port. Thunderbolt 2 ports brought updated wired connectivity and support for six Thunderbolt Displays. Reviews initially were generally positive, with caveats. Limitations of the cylindrical design prevented Apple from upgrading the cylindrical Mac Pro with more powerful hardware. The 2019 Mac Pro returned to a tower form factor reminiscent of the first-generation model, but with larger air cooling holes. It has up to a 28-core Xeon-W processor, eight PCIe slots, AMD Radeon Pro Vega GPUs, and replaces most data ports with USB-C and Thunderbolt 3. Tower (2006-2012) Apple said that an Intel-based replacement for the 2003's PowerPC-based Power Mac G5 machines had been expected for some time before the Mac Pro was formally announced on August 7, 2006, at the annual Apple Worldwide Developers Conference (WWDC). In June 2005, Apple released the Developer Transition Kit, a prototype Intel Pentium 4–based Mac housed in a Power Mac G5 case, that was temporarily available to developers. The iMac, Mac Mini, MacBook, and MacBook Pro had moved to an Intel-based architecture starting in January 2006, leaving the Power Mac G5 as the only machine in the Mac lineup still based on the PowerPC processor architecture Apple had used since 1994. Apple had dropped the term "Power" from the other machines in their lineup and started using "Pro" on their higher-end laptop offerings. As