CPU & MOBO: Wait for AMD to release more s939 cpu's which in turn will increase the number of s939 motherboards. s754 is faster than AXP/P4 but to upgrade now will mean you are buying an already obsolete system. My SUGGESTION would be a s939 3000+ with a nice DFI s939 (yet-to-be-released mobo but any NF3 s939 will do).
RAM: Look for ram with Micron or TCCD Chips: Geil Ultra-X PC 3200, G. Skill TCCD, Crucial Ballistix, OCZ EB/Gold Rev. 3/EL Rev. 2, Mushkin Black Level II v2, PQI Turbo, Adata Viesta PC6000(? Correct me if am wrong here on the new Adata brand name).
HDD: The raptor isn't worth the money. Why pay 200 for 2ms increase? Instead, look at 2x120 Maxtor SATA HDs or a Seagate SATA II HD with Native Command Queuing.
Case: Lian Li PC 65/65B. Stylish, yet simple. An alternative would be a Kingwin lookalike, but the prices will be similar.
Video Card: If you want something under $400 go for a 6800GT for the best price to performance ratio. Also most are easily overclockable to Ultra speeds. If you dont mind spending a tad more you might try for an x800 Pro VIVO in the hopes of softmodding to an XT PE, but by NO MEANS is it a guaruntee that this will work.
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