I have the same problem with graininess. I have been waiting for the render for more than 30 hours. Does it stop automatically afterwards?

I have a intel mac core 2 with 4GB 800MHZ DDR2 SDRAM. Does that mean I'm doomed? I need to use my computer and it's unresponsive when rendering with reality 3. I am so frustrated right now. Do I need a super computer to use this and lighting wise I used 2 meshlights and still it's grainy. I tried 4 lights before and same problem. I altered the iso, shutter speed and aperture but still grainy. I am stumped...by the way, I'm a photographer...beats me...no problem finding the right exposure in real life with my tools, I know how they work. Do I need a new computer. I can't afford a 6 core.

Are the new 3,4-GHz quad-core Intel Core i5 iMacs enough to run reality? Or do I need to run it for 24+ hours?

I took this screenshot yesterday and early this morning changed the iso and shutter speed but still grainy as hell.

I am rendering a Dawn model Maraki with only Eternal Kyra hair and 2 mesh lights (top and front). I am using
iOSX 10.6.8
2.8 GHz intel core 2 duo
4GB 800 MHz DDR2

What am I doing wrong?