Hi, can you show some screenshots just to illustrate better waht yoou're trying to say?

You're welcome mate!!:beer:

Sorry JDigital i gave you the wrong name, i'm used to call it that way because the original Dirt Shader came from XSI. The MR shader for that effect , which is ambient occlusion, is called...

If you have Maya 7, you can find that under the Mental Ray create nodes in Hypershade.
Tell me if you find it!!

This sahder will allow you to make this kind of images. LINK...

The better shader i use to assign to a model, in order to show every detail is the MR Dirt shader. But this is just my opinion.

Before you create any kind of map (color map, bump map, specular map...) you have to unwrap your model, meaning that you have to layout your UVs in order to get a good texturing.
Next you go to the...

You only have 256 mb of ram?! You have to buy more, mate!! 1 gb of ram is the minimum for work with CGI.
Did you tried to use a nVidia card with that same machine? If you did, did you were able to...