Hashcat Server Build

Hello all,

I have been working with oclHashcat on a desktop PC with an R9 280x for several months.
I am looking to build a more powerful PC specifically for running hashcat.
I have reviewed other builds posted on this forum, and used them as a starting point for my build.
Would anyone be willing to review this build and offer any suggestions?
The target for cracking will be mostly NTLM, and MD5.
We're actually under budget (!) with this build, so I have some room to make upgrades. I would like to run a full 4x GPU rig, but I'm not sure if that's an option without using risers. (My searches didn't turn up any motherboards with enough space between cards)
Any help is appreciated, thank you!

CHASSIS: 1x CHENBRO RM41300-FS81
PSU: 1x LEPA G Series G1600-MA
Motherboard: 1x GIGABYTE GA-Z97X-UD7 TH
CPU: 1x Intel Core i5-4690K
RAM: 1x 8GB DDR3 PC3-14900 Unbuffered NON-ECC 1.5V 1024Meg x 64 (Crucial)
HDD: 1x SAMSUNG 840 Pro Series 256GB(SSD)
GPU: 3x PowerColor AXR9 290X 4GBD5-MDHG/OC Radeon R9 290X 4GB 512-Bit GDDR5 PCI Express 3.0 CrossFireX Support OC Video Card