You can change the amount of RAM used for timeline pre-render and RAM previews by going into the preferences/options menu inside of Vegas Pro. It won't necessarily change the amount of RAM required for final rendering, as final renders are usually more hampered by CPU/GPU processing speed than available RAM, but with 16GB to burn it
will speed up your
overall workflow.
Idiot Savant... ok, maybe just Idiot
http://seth.savant-studios.com