You can use multiple CPUs on Windows as of 2001. It won't cut your analysis time in half but I have measured 10-20% improvements depending on the type of model. It is helpful to have 2 cpus so you can do other useful work while mech runs on one cpu. However you will have noticeable slow downs when mech writes to disk and eats most of the ram, especially with big models. I had the most success using remote batches to run big models on workstations (sometimes older, slower ones) that were not being fully utilized. If you don't have that luxury and are running larger modelsthen I recommend dual cpus.
Here's some info from TPI 106426:
In Pro/MECHANICA STRUCTURE/THERMAL 2001 parallel processing is enabled again. Parallel processing allows the engine job to run on multiple CPUs at the same time, with the goal of reducing the elapsed time for the job.
For MEC/S/T 2001, the following platforms support parallel processing:
i486_nt
ibm_rs6000
sgi_elf4
sgi_mips4
sun4_solaris
The sun4_solaris_64 and and hpux_pa64 platforms released on the 2001430 CD do not support multithreading.
To request parallel processing on these platforms set the environment variable MEC_NUM_THREADS. Example:
Unix, csh: setenvC n
Unix, ksh: export MEC_NUM_THREADS=n
Windows: in DOS Shell: set MEC_NUM_THREADS=n
or in the #Control Panel, #System, Environment
where n is the number of idle CPUs on the system. If the Structure/Thermal engine is the only job running on the machine, the number of processors can be selected automatically by setting MEC_NUM_THREADS to "-1". Example for csh:
setenv MEC_NUM_THREADS-1
If MEC_NUM_THREADS is set greater than the number of idle CPUs, the parallel tasks may interfere with each other, and cause performance to drop.
The number of parallel processors requested can be verified at the top of the summary file <study>.rpt. For four-way parallel processing, the <study>.rpt file looks like this:
