There is a hidden (undocumented) benchmark program installed with every AutoCAD (and AutoCAD-based program). You can use it to check the graphics performance of your PC.
The benchmark program comes in the GsTest.arx program file (in the AutoCAD folder). To run this benchmark, first load the ARX application (e.g. with the APPLOAD command) and then start it with the GSTESTBENCHMARK command (type it).
You will get results similar to this:
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Wireframe : 348.897695 ms
Wireframe : 521.642884 fps
Hidden Line : 349.936584 ms
Hidden Line : 520.094235 fps
Flat Shaded : 348.411879 ms
Flat Shaded : 522.370249 fps
Gouraud Shaded : 347.433822 ms
Gouraud Shaded : 523.840768 fps
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Other interesting commands defined in this addon application:
GSAUTOORBIT
GSDEBUG HUD ON