DX 12 gives muc lower general 3d mark test?

[ziki]

I have a system with i7 920 GTX480 and 12GB DDR3 RAM. Yesterday i run a 3D Graphics test with Passmark 9, and gave me a score of 5100 approx. but failed to run the DX12 test it hit some openCL openGL error. I then went ahead and grabbed latest nvidia drivers (385.41) since i hadnt update graphics driver for a couple of year when i boiught that card used, and i was running 2 years old drivers.

Anyway they latest drivers run the DX12 score but the overall score dropped to 4100. Run it again gave me 4200. Why did the score drop 1k points? Was it the latest drivers, or does the DX12 score result in the much lower general score

[David (PassMark)]

Likely the video card doesn't do DX12 and OpenCL very well. Which isn't a surprise, as it is an old card.