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.
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.