The Memory Standard for the motherboard is DDR2 800 and the FSB rate is 1066/800MHz at least according to the motherboard specifications.
so shouldn't both the memory and fsb be at 400mhz for optimal performance?
my cpu-z readout shows fsb frequency at around 200mhz while my memory is at 400mhz, is this some JEDEC standard? if I get my FSB RAM ratio to 1:1 it brings down the memory frequency. is my motherboard capable of 400mhz fsb?
If you want to OC your CPU then yes, you can get excellent performance from a 1:1 OC with both the memory and CPU running at 400mhz. However, if you don't want to OC the CPU and leave it at 266mhz, there is a small advantage to having the memory running faster than the CPU. In some cases it is 2% or so faster to use a 4:5 or 2:3 ratio but, there is no huge performance gain in most applications until you increase the CPU speed.
Sensible OCing with adequate cooling can shorten the life of your CPU but, it should not be a drastic reduction. I have had a 2.4c CPU running at 3.3 since late 2003. But, in general, cooling is essential to longevity and stability. What CPU do you have?