Sources a motherboard makers claim Intel will delay the launch of the X48 chipset from January to February or March because most of Intel's partners still have a large volume of X38 chipset inventory:
The motherboard maker fears that the X48 chipset will slow down clearance of its X38 chipset inventory and has negotiated with Intel to delay the launch of its X48 chipset. However the delay is expected to hurt makers who do not have an overstock X38 chipsets.
Each motherboard maker has already received X48 A1 test samples from Intel and sent back 10 motherboards for debugging. The original mass production schedules were set between the end of 2007 and beginning of 2008.
In addition to DDR3 1600 memory support, the X48 chipset will also support Intel XMP (extreme memory profile) technology, to automatically optimize performance with memory modules that support XMP.