The above calculation was for 32bpp:
3 colors * 1 byte * (8 bits/byte) = 32 bits
3 colors * 1 byte * (8 bits/byte) = 32 bits
FYI, Wikipedia's section on DisplayPort lists the resolution of 5120x2880 x 24bpp @ 60Hz as requiring 22.18 Gb/sec of bandwidth, see http://en.wikipedia.org/wiki/DisplayPort#Specifications