Well the best stuff for A64's is
OCZ VX (bh5 chips) only suitable for boards like the DFI, requires 3.0-3.4v, runs hot
or Samsung TCCD chips-OCZ plat. rev2, Corsair, Patriot, and others.
But most people including myself recommend using value ram on the A64 platform, because, It has been proven over and over that with the A64's onboard memory controller overclocking your ram provides very little performance improvement.
If overall systems performance is what you seek, get value ram for half the price, and spend the money you save on upping the GPU. You will see a much bigger performance
increase in games and graphical applications by jumping up a level in GPU than you will with overclocking your ram.
I myself bought OC ram, OCZ platinum rev2 and its great stuff. But if I knew when I bought for this build, what I know now, I would have went with value ram and upped from a 6600gt to a 6800gt