Socket-A VIA KT133 Motherboard Roundup - November 2000

VIA's KT133 Chipset

With the introduction of the first Socket-A CPUs in June came the introduction of the first Socket-A chipset, VIA’s KT133.  The KT133 chipset shares quite a bit in common with its predecessor, the KX133, in fact, the only difference between the two is that the KT133 supports altered timings required by the Socket-A CPUs. 

The North Bridge used in the KT133 chipset is the VIA 8363.  It supports AGP 1X/2X and 4X, as well as up to 1.5GB of PC100 / PC133 SDR SDRAM.  The VIA 8363 memory controller allows users to run the system memory asynchronously from the FSB, for example running your SDRAM clock at 133MHz while your CPU clock remains at 100MHz.  This allows users to take advantage of their PC133 memory and the added bandwidth supplied by the standard (800MB/sec to 1.06GB/sec) while using 100MHz FSB CPUs.  In the case of the Athlon/Duron, while the actual FSB runs at 100MHz, the bus transfers data twice on every clock, yielding the theoretical 200MHz operating frequency that is stated everywhere. 

For the South Bridge, there are two choices: either the VIA 686A or the VIA 686B Super South Bridge.  They both support five bus mastering PCI slots and on-board AMR slots.  The difference is that the 686A has Ultra ATA 66 support, while the newer 686B boasts Ultra ATA 100 support.  At this point, there are no hard drives with sustained transfer rates of higher than 40MB/sec, so  Ultra ATA 100 support is not that important now.  However, hopefully in the near future that will all change, so it is definitely a plus to get a board with the VIA 686B Super South Bridge. 

In order for the chipset to be properly recognized by your OS, you will have to install VIA’s 4-in-1 driver Service Pack.  If that is done correctly, the AMD / VIA combination is actually very stable and quite high performing.