Intel has for the last 12 months released two different setups of motherboard circuits for the performance segment which have introduced certain complications for motherboard manufacturers. i955X was Intel's first chipset with support for processors with dual cores, while the Pentium D processors of the 900 series which arrived at the end of last year required the updated chipset, i975X. To top it all off it turned out that these motherboards would not support Intel's upcoming Core processors. They needed a minimal modifications of the voltage regulation, but alas an essential such. Abit, together with several other motherboard manufacturers, got stuck in between revisions and uncertainties up until a few months ago when the final chipset specifications arrived. These months of hard work has resulted in Abit's new AW9D and the "MAX" version AW9D-MAX.
Source:Abit AW9D-MAX: Overclocking