We've cleared the board, and it's time for a rundown of the silicon:

Intel Xeon W-2140B (Skylake, 14 nm—likely an underclocked W-2145 to keep the temps in check), 3.2 GHz CPU with Turbo Boost up to 4.2 GHz, paired with what could well be a standard LGA 2066 socket

AMD S5J68 1747 GPEW0333S3 SS63HBN181747US40104 Radeon Pro Vega 56 GPU with integrated 8 GB of HBM2 memory (on-package)

Intel X723D733 E1 05780 (SR3PV?) - likely platform controller hub

AQUANTIA AQtion AQC107-B1-C PCIe to multi-gigabit ethernet controller

Pericom Semiconductors PI3PCIE3412AZHE PCIE 3.0 mux/demux switch

Apple/Universal Scientific Industrial (USI) 339S00428 00012021 Wi-Fi/Bluetooth module

Genesys Logic GL3227A SD 4.0 memory card controller, and Texas Instruments LP8565A13 (likely LED backlight driver)