first off i don't know how you plan on buying ocz EB ddr2. it's been discontinued for quite a while and you can only find it at two places, 2gb overpriced for around $450. the mushkin pc2-6400 is superior to the ocz and it's $331 at monarch (2gb). the corsair is equal quality ram but it's also hard to find and it's price has been inflated. notice that all these rams aren't in production anymore, micron no longer produces the d9 IC's.
so, 1g mushkin pc2-6400 vs 2gb pqi turbo pc2-5400.
400mhz 5-3-3-8 vs 333mhz 4-4-4-12
$188 vs $183
let's assume you have a p5wd2-p and a 670 with watercooling. you have a nice chip and run 4.7ghz stable. 335x14 with lock-free to maximize bandwith. the pqi will do 335mhz at 4-4-4-8 timings. the mushkin will do it with 3-2-2-4 if you give it a little voltage. so bottom line you're paying more than twice as much for ram to lower timings from 4-4-4 to 3-2-2. that's how i considered it when i bought my pqi. i really enjoy having 2gb, but i really want a set of the mushkin for benching.
note: i haven't taken into account dividers, you might want to. the mushkin will probably run ~350mhz 3-2-2, and ~500mhz 5-3-3. the pqi will do about 350-360mhz 4-4-4, ~260mhz 4-3-3. i am not a fan of dividers, they don't do much for real world performance. i'd much rather pump my fsb, run 1:1, and tighten timings.
Best I can do is 225 @ 1:1, 2.5-3-3-7 with max vdimm of 2.9. BSOD or fails to boot with tighter/ looser timmings and more/less voltage.
