Welcome Periscope
My computer is a late 2004 model Dell, and I run SH3 1.4b + GWX3 + SH3 Commander 3.2 + some mods, and everything works quite nicely for me.
To give you an idea of my system:
Dell Inspiron Pentium 4 2.8Ghz, 125MB RAM, ASUS X800XL 256MB RAM graphics card, XP OS.