This may or may not be helpful. I use one thread on my computer for T2 renders. Memory and the fact I have just one computer (I do other stuff while I render, don't tell Oshyan!) makes this necessary.
I bought a new graphics card which supports DVD and BlueRay playback using it's hardware. This has been very good, since I use the computer for movie and TV watching also.
I have found 200 MB for the render cache does not add too much to a 1920 x 1080 render. About one hour is all. This is on a 3gHz P4 HT.
