This Mac Pro is in good shape and runs great! 

May show sings of wear (please refer to pictures).

The 64-bit 22-nm "Xeon E5" processor, or more specifically the "Ivy Bridge-EP" based E5-1680v2, has eight independent "cores" each with a dedicated 256k level 2 cache and 25 MB of level 3 "Smart Cache." It also supports "Hyper-Threading" -- which "allows two threads to run simultaneously on each core" (so OS X recognizes sixteen total cores on this model, eight real and eight virtual) -- and "Turbo Boost" -- which "automatically boosts the processor speed based on workload" up to 3.9 GHz for this model.

If otherwise configured as one of the default configurations, this system originally had either dual AMD FirePro D300 or D500 graphics processors with 2 GB or 3 GB of GDDR5 memory each, respectively. The standard configuration issued April 4, 2017, instead has dual AMD FirePro D700 graphics processors with 6 GB of GDDR5 memory each, which originally only was available as a custom configuration option.

The AMD FirePro D300 graphics processors have "1280 stream processors, a 256-bit-wide memory bus, 160 GB/s of memory bandwidth, and provide 2 teraflops of performance." The AMD FirePro D500 graphics processors have "1526 stream processors, [a] 384-bit-wide memory bus, 240 GB/s memory bandwidth, and 2.2 teraflops performance."

The dual AMD FirePro D700 [graphics processors], each with 6 GB of GDDR5 VRAM, have 2048 stream processors, [a] 384-bit-wide memory bus, 264 GB/s memory bandwidth, and 3.5 teraflops performance."

This system originally supported up to three 4K displays (3840x2160), but on June 16, 2015, Apple quietly increased this official support to as many as three 5K displays (5120x2880) -- two using Thunderbolt 2 ports and one using the HDMI port -- or as many as six displays up to 2560x1600 using Thunderbolt 2 ports.