What Power Supply wattage will go with my computer parts?

tyster

Honorable
Feb 14, 2014
2
0
10,510
I am a first time PC builder and I can't find a Power Supply unit that will power my computer. ALSO, can someone recommend a nice looking/functional PC case for me?? (My motherboard is ATX and I'd like a case to be a Mid-Tower I am having trouble finding one. It will be a PC that runs Minecraft on Ultra Settings and Shaders. Extreme render distance

My Specs:

CPU: Intel Pentium G3420
Motherboard: Gigabyte GA-H87-HD3
Ram: Corsiar Vengeance Pro 2113MHz 2x4 8GB
GPU: AMD Radeon R9 270X
Hard Drive: (Can't find a brand yet, it will be 1.5TB - 2TB though)
PSU: A website calculated it to 300W, but double check if that is right. I would like a PSU 100Watts higher than the recommended (so I have room to grow)

Thanks for any help or advise!