Ya left out an option for the oem ATI drivers... which I use for my HiS X1800XT running at 690MHz core/1580MHz memory...
I find that I can tweak them fine getting
~ 5,040 marks in 3DMarks06
and 10,996 marks in 3DMark05
I use stock ATI drivers and CCC for my overclock. ATITool doesn't work with Sapphire cards, for some reason. I get about 6100 marks on 3dMark06 without a serious overclock. Have gotten higher, but I keep things down a bit for long term stability.