speed up rendering

i got a dual xeon hyper threading and 4 gig of ram. i m under ubuntu.
i actually got some big render to do. what are the setting so as to use the most out of my computer. should i increase the frame split? the 4 threads are running but the ram is not really used. is that normal?
i did try really big render2 but it messed up my picture. did some people know some issue with very big render? when image are cropped or not totally rendererd?

If you’re using ray tracing then you need to understand octree settings. For memory beyond 2GB you need to tell your OS (at least windoze is this way) that you have the extra available and to instanciate the memory upon boot (on your MBR). Render tiles are much like octree settings in that the size of the render AND it’s associated X, Y dimensions (as opposed to the size of the scene iand it’s final render size in pixels, X, Y dimensions don’t matter with octree) must be tested in order to determine the best set up for your particular machine.

You canb find all of this info in the wiki and at other palces on thsi site…sorry, it’s tutorial length info.