How do these i-7 Vs Dell Workstation Compare ?

How do following 2 systems compare when it comes to computing power ?

I will be connecting 12 Monitors to each system by installing 3 ATI FirePro 2460 Cards each supporting 4 monitors.

Which one of following two would you choose ?

(1) I-7 Desktop :

Intel i-7-2600K 3.4 GHz Processor

Asus WS Revolution motherboard with 4 PCIe x16 slots

16 GB G Skill Ripjaws OR Corsair Vengeance DDR3 1600 RAM

760 Watt Seasonic Gold Modular power supply

Corsair Obsidian Series 650D (CC650DW-1) case

500GB SATA (7200 RPM ) HDD

Windows-7 64 bit ( Ultimate )

OR

(2) Dell Precision T5500 System :

Single Intel Xeon E5645 2.4 GHz LGA 1366

Intel 5520 Chipset & Dell MOBO with 4 PCIe x16 slots

Integrated Broadcom 5761 Gigabit Ethernet Controller

12 GB (6x2 GB) DDR3 RDIMM Memory, 1333MHz, ECC

500 GB SATA (7200RPM) Hard Disk Drive

Windows-7 64 bit ( Ultimate )