As for PSU , you can get a used 350W Antec PSU which is around $23 . Even if you add a graphic card like EVGA GTX 750 , 350W is plenty
http://www.amazon.com/Antec-Basiq-BP350-Power-Supply/dp/B000H9J3ZC/ref=sr_1_7?s=electronics&ie=UTF8&qid=1444649366&sr=1-7&keywords=300w+power+supply
or alternative Delta 300W PSU $13 . You may not know Delta but Delta doesn't make standalone PSU , all of their PSU are made for Acer , IBM , Asus .....Basically , OEM manufacturer. I bought it for my APU machine
http://www.amazon.com/Delta-300-Watt-Power-Supply-DPS-300AB-15B/dp/B0049D774G/ref=sr_1_15?s=electronics&ie=UTF8&qid=1444649366&sr=1-15&keywords=300w+power+supply
http://www.amazon.com/Antec-Basiq-BP350-Power-Supply/dp/B000H9J3ZC/ref=sr_1_7?s=electronics&ie=UTF8&qid=1444649366&sr=1-7&keywords=300w+power+supply
or alternative Delta 300W PSU $13 . You may not know Delta but Delta doesn't make standalone PSU , all of their PSU are made for Acer , IBM , Asus .....Basically , OEM manufacturer. I bought it for my APU machine
http://www.amazon.com/Delta-300-Watt-Power-Supply-DPS-300AB-15B/dp/B0049D774G/ref=sr_1_15?s=electronics&ie=UTF8&qid=1444649366&sr=1-15&keywords=300w+power+supply
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