Can I make this work and what else should I get?

Hi guys, I've gotten tired of waiting for a new mac mini and also disconnecting and reconnecting my macbook pro.

What I have lying around: Supermicro X8DTL-iF 2x Xeon E5620 2x Artic Cooler Fans 2x 1tb hdd

Would I be able to make this work or would I be better off buying all new components? Cost wise, if the old build works, I figure I'd need another $100 worth of stuff (psu -20, ram - 20, case - 40, gpu -?20?), while I figure the new build will need at least $400.

Thanks for any suggestions.