The Macintosh IIvi was a short-lived model of the Macintosh II series of Macintosh computers from Apple. The IIvi included either a 40, 160, or 400 megabyte hard drive, three NuBus slots, and a PDS. The IIvi was essentially a Macintosh IIvx with a slower processor (16 MHz vs. 32 MHz) and no floating point unit. The Macintosh Performa 600 is essentially an IIvi with the IIvx's 32 MHz CPU.