Actually, ATI always insisted that they had full open GL support but it wasnt't true. Many of us had artefacts, including me, when dealing with even hi end ATI cards, in 2001 2002 when I started using SketchUp. ATI support swore they had full open GL support and Jim Holman from SketchUp support remained firm that they did not. I purchased and Nvidia card at the time and all artefact problems cleared. It was explained to me by Jim that ATI only used a subset of open GL at the time, that was necessary for gaming but not everything that was required for 3D modelling applications. So if your ATI card worked for you in 1998 perhaps you just had a fortunate configuration at the time. But I can assure you that it did not work in mine and in many many others.