Why so much? I understand you may want to make it future-proof, but you are pushing it rather too far.
24GB of RAM? 7TB of HDD space? 2 x GTX 590? By halving those, you can save a fair bit and still be future-proof.
Nonetheless, I am jealous of what you are planning on building. You'd want a surge protector, in case power cuts out and it blows something up.