Is 200MHz a noticeable bump in real-time performance for a C2D system?

[Kaiju]

Okay, so you can get a E4300 to 3GHz using a 333FSB x9 (theoretically) with Geil's PC5300C4 4.4.4.12 RAM timings @ £111 on OCUK. I've tied that with a P5N-E Asus board and an AC7 cooler for roughly £330inc shipping.

So what i'm wondering now is...

Would the extra cost (roughly £70) for a E6400 and some Geil PC6400C4 @ 4.4.4.12 be worth the 200MHz extra overclock using 400x8=3.2GHz?

Of course there is no guarantee on how each chip will clock, i'm predominantly basing my idea on RAM timings as I don't want to buy RAM that won't overclock.

 

[Kaiju]

As Graeme43 stated, he doesn't see a significant benefit past 3GHz, so even though the overclocking options would be better with a E6400 and PC6400, a E4300 and PC5300 would be £70+ cheaper and could hit 3GHz.