Which Socket 939 chipset is fastest?

I'm looking at building a home workstation around an Athlon 64 X2 and socket 939 motherboard. I'm not a gamer and I won't be overclocking the CPU. The system will be used primarily for audio and video ripping, encoding and decoding.

Disregarding video performance, which chipset is considered fastest at things like memory throughput, hard disk throughput, etc.?

Would running onboard video on a board that offers the option have any effect on these things or would it be best to run a PCI-X video card to get any video traffic off of the other buses and/or CPU?

Memory throughput isn't on the chipset in AMD64 architecture.

That figured, chipsets are reduced to being mere I/O clients. Performance differences are largely irrelevant, but if you like negligible deltas, SiS have the best harddisk throughput, NVidia got AGP a hair faster than anyone else and the only integrated Gbit ethernet of the bunch (but have the only chipset that requires a cooling fan), VIA excels on USB throughput, and ULi have the highest chip integration and the lowest power consumption.

Oh, and PCI-X is not PCI Express. Thank you.

The most recent Maximum PC magazine compared three 939 chipsets and held all other components constant. On a variety of benchmark tests, it found the nf4 chipset the fastest, followed by the via 890, with the ati crossfire bringing up the rear. The differences between the 3 were not that great. The surprise was that the crossfire fared worse than the via 890. BTW, the tests were at default settings, and so overclocking potential was not assessed.

The NVidia chipset coming out "fastest" is because all NVidia chipset mainboards I've seen have the default system clock set to 200.9 not 200.0 like it's supposed to. That'll be the .5% performance "advantage" seen in those benchmarks.

the Nforce professional has a TCP offloading engine built into it. That makes it a good bit better than Nforce4 for network connectivity.

the Nforce4 SLI is probably the best all around chipset.

Initial reports on ULi (or is that now nVidia? ) 1697 look extremely promising.

yes it does. still, the network performance on nforce3/4 is unmatched on the desktop.