Which memory for this build?

[p3matty]

Building a new rig with Christmas money, and have everything picked out by the memory.

Intel Core 2 Duo 6300 - $191 (recent spike in price?!?!)
Asus P5N-E SLI - $130
Vid Card - EVGA 7600GT $110-$120 after mail in rebate (what's the difference between N615-TX and the N554-AX? The only thing I can see is the later is slightly overclocked and has 2 DVI ports rather than one DVI and one VGA. Is that it? Is that worth the extra $10?)
PS - Antec NeoHE 500 - $75 after mail in rebate
HD - Seagate Barracude 320GB - $95 (though I might recycle an IDE HD from my current rig instead. Bad idea?)

Total thus far - $601-611 (or $506-516 without new HD).

Now for the memory -
Corsair 5400C4 or Corsair 6400C5. They are $109 and $124 respectively.

If my thinking is right, I should be able to overclock the 6300 to 2.3 GHz (333 FSB x 7), and the 5400 will be running at its rated speed and at C4 timings. The 6400s will be running below rated speed, but still at C5 (so slower, right?). I should be able to go up to about 2.5GHz with the CPU and keep the C4 timings on the 5400, right? Why spend the extra $15, or am I missing something here? Even when 1333 FSB quad CPUs come out, the MOBO will handle them, and the 5400 memory will be running at rated speed, right?

Any other suggestions to save a few bucks would be appreciated. Thanks.

 

[MrMr]

Well the 6400, if running below it's rated speed, can run at 4-4-4-12 also. Difference being that you can run it at 5-5-5-12 stock for an overclock of 2800MHz. A few extra volts will allow it to run at 450 for an overclock of 3150MHz (most likely at 5-5-5-15). You won't get that with the PC5400. And the speed increase will more than compensate for the slower timings.
Or you can just get this and ensure the best overclock possible.

http://www.newegg.com/Product/Product.asp?Item=N82E16820134016