In the last year, NVIDIA has risen to the top of the AMD Athlon 64 chipset market with their nForce series of single-chip solutions. As Socket 939 has matured, nForce4 has gained the dominant position in the AMD motherboard market. VIA, who has never been able to ship a competitive solution to NVIDIA’s SLI, has moved down the pecking order somewhat, and is now more regarded as a value chipset, along with SiS, in the Athlon 64 market.
This is an amazingly in-depth article if you want to know which nF4 Ultra motherboard to buy. Check it out at AnandTech.