i wouldnt suggest on memory overclocking, even if ure dat familiar with mems and voltage. it takes mor dan guts to raise d 800mhz. at 800mhz, d cas4 is common. d 1066 at cas6 is also d most common.
it would still depend on d user though, but i really wont suggest OC'ng the memory. ure choice...
downclocking maybe...