Should I buy ddr2 1200 memory since I'm going to overclock my system anyway.

[moto211]

so, after reading this thread, i have a few questions regarding my upcoming build. what do you guys think will be better for a Q6600 build if i'm shooting for 3.6Ghz (400x9)? i'm considering 2x2Gb dual channel DDR2-1000 with timings 5-5-5-15. I figure that if i run this ram at 1:1 then it will be underclocked and i can try to tighten the timings to 4-4-4-12. who knows, i might be able to tighten them even more than that. or, do you think it would be better to just use 2x2Gb dual channel DDR2-800 with stock timings of 4-4-4-12?