H77 has a few more features for a bit more money, maybe he saw the B75 and it's all he needed.
@UnfeeKecleon - RAM isn't...in a sense "consumable". You'll never actually "run out" of it.
You can get the 7870 or 7870 GHz Edition if you want.
All 7870s are GHZ edition. They are stock at 1000MHz.