In 90% of the cases where it runs slow it's because of the lack of OpenGL drivers on you computer. First make sure that your videocard supports OpenGL (One of the following cards should work: Any nVidia card [TNT, TNT2, GeForce], ATI Radeon, 3dfx Voodoo 2..5, but also a lot of other cards). The problem is that you ussually don't get OpenGL drivers when you install the drivers for your card. The standard drivers are the software OpenGL drivers made by Micro$oft which are VERY slow. Your best bet would be to go to www.glsetup.com and see if you card is supported. If it is you should download the install programm and install new OpenGL drivers. This should alleviate the problem.