memory settings on an ASUS P5W DH Deluxe

I am trying to 'tune' the settings of my memory on this board.
see sig below.

CPU-z has my 'spd' as c4 timings
CPU-z has my'memory' at c5 timings

FSB is at 333
Memory freq is set at DDR2 800
FSB: Memory ratio is at 4:5

The ASUS mobo has the following settings for performance
Auto, Standard or Turbo

Cannot find any place in the bios to set the timings to c4 rather than c5

Another question,
would it be faster to have a 1:1 FSB: mem ratio
and c3 timings?

thanks

Thanks

I will give that a try.
I have already set the mem voltage at 2.1v per Corsair specs

I think it is 2.1v