This is a system I just put together last month. This is a large desk-side system (aka tower) on coaster wheels with hot-swap brackets for up to twenty 3.5" drives plus up to eight 2.5" drives.

The main chassis is a Xigmatek Elysium case, hacked to allow for large (2") coaster wheels, optical drive tabs cut off to hold four 3.5" hot swap chassis, and the second PSU bay opened up to hold an extra 2.5" hot-swap chassis. A RAID controller with internal 24 ports drives the HHDs. The graphics adapter allows connection of up to for up to 4 monitors via Displayport connection.
I am getting 1 Gigabyte/sec speeds when copying large files RAID6 to RAID6.

I am unable to list the some components in the "Hardware" section ("no results found"), so I list them here for now:
(1) nVidia Quadro NVS 450
(1) Areca ARC-1883IX-24
(4) Supermicro CSE-M35T-1/B (stock fan 92mm replaced with Nexus DF1209SL-3 for quiet operation)
(1) SUPERMICRO M28SAB (stock fan 40mm replaced with custom-mounted Noctua NF-A6-25 PWM for quiet operation)
(1) Samsung 840 EVO 500GB
(10) HGST Ultrastar HE 6TB (in RAID 6 with hot-spare for a usable capacity of 42TB)
(9) HGST Deskstar 7K4000 2TB (in RAID 6 with hot-spare for a usable capacity of 12TB)
(5) Sandisk Ultra II 960GB