Hmm... The problem with a board with both memory types (such as the ECS you list) is that even when coupled with DDR, it's not going to be much of a performer, and you'll be stuck when it comes to upgrading as it won't support faster bus speeds than 133(266DDR), which'll limit you to (IIRC) an XP2400+ CPU at best in the future (actually I think there were some rare 2600+ chips that ran @133FSB).
But given the choice between that ECS and a VIA KT133 board, I'd go with the one you suggest, as it should be ok I guess, and will certainly be a lot faster than your PII system. (although Halo is a hell of a performance hog for what it is :frown: )
I I was you, I'd only buy a 'combo' motherboard to do something like this:
1) Buy duron + mobo, use existing RAM
..Save for a little while..
2) Replace RAM with some reasonable DDR
..Save again for a while..
3) Replace motherboard with a nice nforce2 model
..Save some more..
4) Buy a Low-end Athlon XP & overclock it loads.
That way there's no single huge outlay of money, but it does end up costing more.
But like I say - it WILL be a lot better than your current rig, and if it's a good deal you'll probably be ok.
What other motherboards where you looking at?
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Epox 8RDA+ rev1.1 w/ Custom NB HS
XP1700+ @205x11 (~2.26Ghz), 1.575Vcore
2x256Mb Corsair PC3200LL 2-2-2-4
Sapphire 9800Pro 420/744