The HC-90 and HC-95 are very similar in terms of hardware. They both have two CPUs, the familar z80 and an HD-64B180 which runs at 6.144 MHz. The other common features include 64KB of RAM, 128KB of Video RAM, at least one 720KB 3.5" Floppy disk drive, and an RS-232C. From CompuWiki, a Wikia wiki.