This is really the answer. From about 1990 to 1996, RISC workstations were several times faster than PCs, especially in floating point performance. However, w

This is really the answer. From about 1990 to 1996, RISC workstations were several times faster than PCs, especially in floating point performance. However, when Intel came out with the Pentium Pro in 1995, it had better integer performance than almost all of the RISC chips and was about even on floating point. With Windows NT and Linux being viable operating systems for the sorts of applications people used workstations for, it was only a matter of time before workstations died out. The main thing holding back Intel machines by 1996 or so was software support for workstation type applications such as EDA and CAD tools, but this was sorted out within a few years. The last holdout was SGI, which was used in the visual effects industry, but NVIDIA caught up to them in about 1999 and SGI gave up on its performance leadership, and the applications followed.