Please explain what running SW "Open GL" means. I have noidea. I have a brand new computer, and SW3 loaded, and when I amrunning my SW in Open GL mode the dimension tool works fine. When Iturn off the "Open GL" option, my dimension tool seems to have areal problem highlighting and picking up the lines on a drawingthat I want to dimension to. Is this something to do with the videocard? If so, what? I did a web search, but didn't get any clearlydefined answers. The new computer, running XP professional wascustom built by Dell to run Solidworks, but they messed up and putin a nVideo NVS card instead of the NVidia Quadro FX570 card theywere supposed to. They are shipping me a new video card, but Idon't understand this "Open GL" thing. I have been runningSolidworks for 7 years now, but never had to use this Open GLoption before. Would this have smething to do with the video cardthat came in this new machine?---BrianSolidworksGeneral