Shader Model 2.0

I have a program that requires Shader Model 2.0 or higher . When I load this program it gives me an error of
"Device must support Shader Model 2.0 or higher , program will exit now"
What do I need to do to get this ? Is it even something that you can upgrade and get ? How Do I check for it ?

I am using a :
Dell Optiplex 170L
Windows XP

Specs Here :
http://www.dell.com/downloads/us/pro.../170L_spec.pdf