OK so I was watching the video on the 1300 dollar build and it said to get Mushkin black line 16gb (4x4gb) ddr3-2133. But on pc part picker it says the cannas 4 memory slots but it says 8 are needed. I'm pretty sure the site is just retarded but I was just checking.
It says the motherboard has 4 memory slots*
The best thing you can do is check the Asrock site for compatible memory and pick one from their list.
Here: http://www.asrock.com/mb/Intel/Z77%20Extreme4/?cat=Memory
The most likely reason that pcpartpicer says that it needs 8 slots is because its a qwad-channel memory kit, The it the only thing that would happen if you put the four dimms in you asrock board, is that it would run in dual-channel mode which would work perfectly
ok thanks guys