I think this is just a basic question ;)

If my FSB is 800mhz (E5700 on Asus P5G41C-M-LX)

And i have upgraded to 1600mhz memory (Crucial CT51264BD160B)

Can i change my memory frequency to (800 DDR = ) 1600mhz?

Currently on Auto settings the memory works fine but CPU-Z shows FSB:DRAM 1:2
DRAM frequency 400mhz (so actually 800mhz)

Can i change Memory frequency in BIOS from AUTO to 800mhz and expect it to work as it is a multiple ?
Would the timings self adjust on Auto/SPD or should i manually set them as shown in the SPD timings table on CPU-Z?

Thanks for any help, cheers, Tony.