If your AutoCAD Graphics Performance dialog shows gdi16.hdi instead of a specific video card (like NVIDIA or AMD), it is usually due to one of the following:
: Type GRAPHICSCONFIG and ensure "Hardware Acceleration" is turned ON . autocad virtual device gdi16.hdi
The gdi16.hdi file is a fossil from the era when CAD software transitioned from dedicated Unix workstations to the desktop PC. While it is functionally obsolete in modern 64-bit CAD environments, its existence reminds us of the crucial role the Heidi Device Interface played in standardizing CAD plotting. It bridged the gap between the precise world of vectors and the printer on your desk. If your AutoCAD Graphics Performance dialog shows gdi16