| I'd take the ASUS board. It will allow you to easily upgrade video in the future, which should be all you need to do in the next 2 years or so, should you want decent gaming.
Do you need to buy harddrives or optical drives? RAM? I assume you need a vidcard too...
Although 939 offers dual-channel, there is not much difference between 754 and 939. You can still get a 3000+ winchester on 754, but it may not offer 64-bit functionality, but could lower you overall cost. Check out the 3dmark scores in my sig...out of all a64's and x800xt's that are in the 3dmark ORB, i am on page3, so almost in the top20 fastest out there...and noone else is on 754. I know that the overclocking that has happened on 939 is very promising, but i'm about to try out a winchester on my platform, and see if it scales as well. Might be something to keep in mind.
If you do not plan to go windows64, then the sempron line may be your best bet. You get the same functionality as the a64s, processing wise.
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