Please tell me that before you went out to buy more RAM because your system didn't boot, that you tried resetting the CMOS/BIOS to default first...
a lot of newer overclockers make this mistake - think there is a serious problem and that they won't boot for good - so you may have just bought new RAM without even needing to.
Sorry if I misjudge you, but I'm just wondering if you're new to overclocking or not. One can not simply tell by number of posts or join date
Anyway, I'd go with something loose liiiiiike.... oooh, umm... 3 - 4 - 4 - 8 should do the trick? I'd wait til someone else comes in and gives you an opinion though, because I'm not the most experienced of overclockers. It's worked for me doing that though.