I chose the P5B Deluxe over the 975 for the increased SATA/RAID capability. If you don't need that, buy the one that fits your needs. Great board, BTW.
With that setup, I would recommend a 500W power supply.
You can't use DDR RAM in either of those boards. The Corsair is a good match with the ASUS boards.
I just built my first new system in many years. The going in advise I received was don't skimp on the power supply or motherboard. Good advise. I will add that a high quality case is a must as well. I recommend Lian-Li. Of all the fancy new piece parts I bought for the new super computer, the case is my favorite and will be around for a long time.
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