SSE instructions are single-input, multiple-data (SIMD) instructions that allow the CPU to perform more operations in a given number of clock cycles. Dalex's SSE driver appears to simply break up the SIMD instructions that the processor does not support into standard instructions that the CPU can understand. It completely ruins the speed advantages of SSE but allows a machine to run a particular compiled binary program that the CPU otherwise wouldn't be able to run (such as Dalex being able to run Adobe programs.) I have not run a program like this as all of the CPUs I am using support at least SSE. Plus, I have the source code to almost all of the programs I run and could just recompile without an unsupported SSE instructions and it would likely end up faster than using the SSE emulation program.