ALi has launched a North Bridge part that supports the Pentium 4's 800MHz effective bit rate frontside bus, courtesy of the company's ULi subsidiary.

The chip, dubbed the M1683, provides support for up to 400MHz DDR SDRAM - installed on no more than three modules - in a single-channel configuration. It also provides an AGP 8x graphics bus.

Interestingly, the M1683 uses a 1.6GBps HyperTransport bus to communicate with the host's South Bridge chip. ALi is touting its M1563 as the part of choice. But unlike chipsets aimed at the same roles, such as VIA's just-announced PT800, and Intel's 865 and 875 lines, the M1563 doesn't support Serial ATA.

Some observers have seen that as a limitation, but while Serial ATA is establishing itself at the high end, its questionable whether it's ready to supplant parallel ATA-133 just yet. For that very reason, almost all Serial ATA P4 chipsets also support the older spec.

The ALi South Bridge also supports all the usual I/O options, including 10/100Mbps Ethernet, USB 2.0, legacy ports, AC97 and PCI. It also offers Memory Stick support and HomePNA networking. ®