The present invention provides an image/graphics data display mechanism for continuously displaying image/graphics data on multiple display devices of a computer that contains a system memory directly accessed by the computer's CPU during the CPU's power saving non-responding period, wherein there is provided sufficient system bandwidth, the mechanism of the present invention is independent on the resolution running on each display device and the number of display devices connected to the computer system. The mechanism provides two approaches to achieve continuous display of image/graphics data on multiple display devices computer system. In the first approach, a common clock source is used to coordinate display device horizontal synchronization signals, vertical synchronization signals, horizontal blank periods, and vertical blank periods. In the second approach, the mechanism has a control on the lengths and occurrences of the display device blank periods.