Today I had a request for processor speeds, clock, RAM size, and the type of framebuffer for a Sun Blade 2000 workstation. I used the prtdiag command to get this information.
Here is the path.
# /usr/platform/sun4u/sbin/prtdiag -v
If you want the CPU speed(s) only:
# psrinfo -v
If you want RAM only:
# prtconf | grep Memory