protected system memory and except for the physical vram depth limitation on data structures which are expected to be shifted out the s port of a video ram the restrictions on where various portions of a software application may be located in system memory are minimal in one embodiment in a minimum system with only one megabyte of system memory vram the low 64 k 32 bit words might contain cpu instructions and data the next 300 k bytes might contain compressed image source data and the next 172 k bytes might contain audio and other data the next 150 k bytes might be allocated for one frame buffer 320 by 240 pixels by two bytes per pixel and the last 150 k bytes might be allocated for a second frame buffer frame buffers are arranged so that even numbered data lines reside in the left memory bank and odd numbered data lines reside in the right memory bank pixels are represented as 16 bit values divided as follows five bits to represent a red pen number five bits to represent a green pen number four bits to represent a blue pen number and two subposition bits h and v in an alternative data format either the h bit or the v bit may be replaced by a fifth blue pen number bit when a pixel value is transmitted down the display path a color look.