Comes with 512K of VRAM in the form of two 256K SIMMs. Versions of the computer which came equipped with a CD-ROM player often had 1MB of VRAM pre-installed. A 1MB VRAM configuration is achieved by replacing the two 256K VRAM SIMMs with 512K SIMMs. Will not support 1-bit video on the Macintosh 12 inch RGB Display.