Mode X is a hybrid display mode derived from the standard VGA Mode 13. This mode allows the use of up to 256K bytes of display memory (rather than the 64K bytes allowed by Mode 13) by using the VGA display adapter's EGA multiple video plane system. On Windows 95, DirectDraw provides two Mode X modes (320´200´8 and 320´240´8) for all display cards. Some cards also support linear low-resolution modes. In linear low-resolution modes, the primary surface can be locked and directly accessed. This is not possible in Mode X modes.
Mode X modes are not currently supported on Windows NT. Linear low-resolution modes are also largely unsupported.