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 E5-1650v2, has six independent "cores" each with a dedicated 256k level 2 cache and 12 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 twelve total cores on this model, six real and six virtual) -- and "Turbo Boost" -- which "automatically boosts the processor speed based on workload" up to 3.9 GHz for this model.

This system has dual AMD FirePro D500 graphics processors with 3 GB of GDDR5 memory each. This graphics processor has 1526 stream processors, a 384-bit-wide memory bus, 240 GB/s of memory bandwidth, and provide 2.2 teraflops of performance. However, if a "Six Core" processor option was selected as a CTO upgrade for the entry-level ME253LL/A model, it originally was possible to configure this system with slower dual AMD FirePro D300 graphics processors.

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.