I have noticed a issue on several of the computers I have upgraded to SolidWorks 2010. After completing the upgrade of Solidworks 2009 SP 5.0 to Solidworks 2010 SP 4.0 (this is a upgrade, not a clean installation) in some cases SolidWorks does not correctly identify the OpenGL Video Card. I was getting some complaints from several of my Designers that they had degraded graphics performance on there systems after I upgraded them from 2009 to 2010. As it turns out, for some reason, solidworks did not correctly identify the video card and was using software OpenGL rather than using the OpenGL Video Card to process the graphics. It took a bit of investigation to determine this, but if you are having unexplainable graphical issues in SolidWorks go into your options, under performance, and make sure that software open gl is not checked or grayed out with a checkmark. If the option for "Use software OpenGL" is grayed out with a checkbox, but you know you are using certified Solidworks graphics card, you are probably having the same issue.
I thought it possible that the driver that I was using for these machines were not "Certified by Solidworks" (the graphics cards are as follows: Nvidia Quadro FX3700, Nvidia Quadro FX1500 and ATI FirePro V8700), but after a check using dxdiag from the run command it turned out that in fact they were all qualified on the site; http://www.solidworks.com/sw/videocardtesting.html.
Anyhow, to resolve the issue, I had to uninstall the old driver off of the computer and then reinstall it, even if you are installing the same version driver as previously installed. Simply reinstalling the driver over the top of the old one, without removing it first did not allow Solidworks to properly detect it. I hope this helps someone out there, but it definately made my designers much happier, beleive me it is a night and day difference using Solidworks in Software OpenGl mode as oppossed to using that $800.00 graphics cards we have purchased.