<< You mention VIA and Stability in the same sentence. Bad idea 😀
IMHO, the most stable P4 chipset is SiS 645. Why not i850 or i845/845-D? Because of the PCI issues which have only recently seen the light of day. And perhaps the incompatibility with certain (older) AGP graphics adapters.
For Socket A (Athlon), I'd have to give the nod to AMD 762/766. SiS 735 is certainly a contender as well. (AMD761 is certainly a choice also, unfortunately, good luck finding a board that pairs 761 with 766. They all use VIA's 686B.)
As for VIA's efforts in either camp ... I'd avoid them like the plague. YMMV. >>
i have an asus a7v133 and it has given me nothing but trouble. it doesnt reboot, period. you have to shut down and then power back on. if you try to reboot, it will shutdown, then the screen will stay black, and you have to cut the power via the psu, and when you turn it back on, it gives you a warning about your fsb being wrong (its not, it does this regardless, even @ 90fsb, cpu underclocked.) and it locks up all the time in windows. good thing i use linux mostly, its rock solid under linux.
the thing that sucks about 761 boards like pabster says, is that they all use the 686b southbridge, which is the southbridge from hell. really sucks. my next system will be an nforce 420 (or something similar, i might not upgrade for a while), if its not stable, then matrox+intel, here i come!!!!