KG7 is VIA South bridge, the notorious 686B and really, I think it should be avoided.
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Hmm, what about the Leadtek 735 solution? When's it coming out (or is it out yet?) >>
It's out and I've heard very bad things about it. Should be avoided.
IWill XP333-R is a great board and I'd definately consider it, but personally, I would either wait for nForce 415 or consider getting the allready avialable MSi K7N420 Pro. it is at the same price range as Dragon+, A7V266-E, and KR7A-RAID($146 at Newegg), has On-Board 5.1 nForce APU, On-Board LAN, and now with the latest BIOS, SuperStability can be turned off so that is no longer an issue, it's stable, and we all know nViida's wonderful drivers so, there would be a good arguement for XP333-R but, I think you should definately consider nForce 415-D or getting K7N420 pro.
As for SiS 745, well I have not heard too much. ECS K7S6A is out, but it has no SDR slots, and no LAN unlike K7S5A, and very poor ocing (better than K7S5A, but still poor) and really, there are only 2 other confirmed SiS 745 boards coming, and those are Abit KS7 and MSi 745 Ultra (see my thread
here. So, don't hold your breath on SIS 745