2003-04-22 Via K8T800 Opteron (Hammer) chipset. K8M800 is pin compatible, but with added UniChrome2 graphics. Formerly known as K8T400M.
2003-05-13 Via KT600 Athlon chipset, based on the KT400A, but adding 400 MHz front side bus support. Also known as KT400A-CE.
2003-07-02 Via VT8237 South bridge for Via chipsets, and the Ultra V-Link interface. Succeeds the vt8235 south bridge.
Supports 6 PCI slots, 8 USB 2.0 ports, 10/100 Mbps Fast Ethernet, 2 S-ATA ports, 2 P-ATA ports, RAID 0, RAID 1, RAID 0+1, JBOD (SATA) and Via "Vinyl" audio 6 channel audio.
The predecessor, VT8235, was identical, except for the S-ATA support.
The VT8237CE, launched in 04-Q1, adds Ultra V-Link support for 1 GB/s connections to the North Bridge. An updated VT8237s with SATA-II support (3gb/s) will launch in Q3 2006.
2003-11-07 Via PT880 Pentium 4 chipset previously known as PT600 supporting the 800 MHz bus. Identical to PT800, except for an added second DDR400 channel. Includes QBM 533 support, which seem to be two DDR channels with one delayed by 90 degrees. Uses the VT8237 south bridge. There will also be a PM880 version with added UniChrome graphics launched in 04-Q1.
2004-Q3 Via VT8239 South bridge pin compatible with the older VT8237, now including 4 S-ATA channels and SATA Advances Host Controller Interface (AHCI). Also adds 96kHz, 20 bit Azalia audio.
One may wonder why the 8239 is necessary as VT8237CE fills the short term needs and VT8251 adds PCI Express. Now canceled or renamed to 8251.
2005-01-31 Via PT894 Pentium 4 chipset earlier known as PT800 / PT890 supporting the 1066 MHz bus and 666 MHz DDR2. Uses the VT8237, and VT8251 south bridges. Includes PCIe x16 support while the PT894PRO version will include 2 PCIe links (to be run as x16 + x4 or 8x + 8x).
There will also be a PM890 / PM894 version with added DeltaChrome IGP (previously known as UniChrome 3) graphics launched later.