This logo is designed by Scott Kim. Scott Kim website.
Silicon Graphics's famous logo is a corner perspective of a tubed cube. The key behind this successful logo lies in the illusion it imparts. A cube appears hexagon when viewed from a corner.
A spinning sgi cube. The SGI cube is sgi's hallmark and trademark. Its perspective illusion and rendering symbolizes the company's craft. In early 1990s, SGI is regarded as the king of computer graphics.
Around 1998 SGI is bleeding to death, with graphic CAD systems happily running on cheaper but not slower Windows/Intel and Mac's PowerPC chips. They changed their logo to a stylized SGI and dropped the iconic cube. Later years, due to complaints, they re-adopted the old cube logo.