Intel will officially start delivering its X38 chipsets in mid-September, enabling motherboard makers to begin volume production of X38-based motherboards by the end of this month. The official launch of the X38 chipsets will also come in time to compete with AMD's forthcoming RD790 chipsets scheduled in November. In addition to supporting 1333MHz FSB, DDR3-1333 memory, PCI Express 2.0 and dual PCIe x16 graphics slots, the X38 will also be the first core logic chipset using ISH (integrated heat spreader). While barely beginning shipments of the X38, however, Intel also plans to launch an upgrade version of the chipset, the X48, by the end of the year with motherboard makers to begin delivering X48 motherboards to shelves in the first quarter of 2008, according to Intel's roadmap. The X48 eventually will come with the same chip design as the X38, but will support 1600MHz FSB and DDR3-1600 memory. Board makers will not be required to change any design work of X38-based motherboards since the X38 and X48 chipsets will use the same PCB.