3ds max will use all the memory you can give it. You need the best graphics card you can afford and the most memory you can, or just be patient. Rendering is a very intense process. Check out some of the rendering times studios need. Producing a CG film
A typical 90-minute film shot at 24 frames per second results in 130,000 frames. Each
frame is broken down into elements for rendering purposes – the characters, rocks,
trees, clouds – which are composited into the frame. Rendering a single element having
a complex geometry (a character with realistic looking fur for example) and taking into
account lighting effects can take a few hours to compute. It is little wonder that 17.7
million hours of rendering time (approximately 2,020 CPU-years) was required in the
making of the film.
CPU CPU CPU, RAM, RAM RAM. If you are using this for business, you need to keep upgrading your CPU to the latests pretty much yearly to see speed boosts. You may also check on how to make a multi-node system.