Can anyone help me set my RAM to its native 1066 speed

hi all i have some kingston hyper x 1066 ram 2x 2gb that defaults to 800 when installed, im not to sure how to go about setting it to its native 1066 speed and was wondering if someone could help me. I understand that upping the fsb would increase the speed of my ram but i have an PII 955 BE so i do not use the fsb to oc i just use the mulitplier. The motherboard i have is the asus m4a785d m pro
http://asus.com/product.aspx?P_ID=yCI8UenairUZJWET

I have had a look in the bios but got kinda confused with all the settings

If someone could help id be very gratefull

many thanks

Not sure on your board, however, there should be a ram divider. You might have to tell the bios to manually set your RAM somewhere to open it up for change.

Set Memory Clock Mode to Manual, then Memclock Value to 533MHz.

This is what i have done and it resulted in my machine posting an error message that i could not make out. I went into the bios and changed my memory clock value to manual and set it to 533mhz which with ddr2 ram should then give me 1066mhz, there is no where in my bios where i can change the fsb:dram ratio tho. Then i get the option to set my dram timing mode to auto or dct 0 or dct1 or both, i set it to both and then changed TCL to 5 TRCD to 5 TRP to 5 TRAS to 15, i then also set the voltage to 2.2v which the kingston memory states, but for some reason i just got the error message and my computer froze what am i doing wrong?

The only thing i can think is my motherboard states if i run my memory at 1066mhz i can only have 1 stick per channel i have both my sticks in slot 3&4 on the board which are the same colour and according to cpuz is running in dual channel mode, the strange thing is in the manual it states that channel A is dimm A1 and dimm A2 which according to the motherboard manual diagram is slot 1&3 going from left to right and channel B is dimm B1& dimm B2 which shows again on the diagram as slot 2&4, as i stated my memory is in slot 3&4 which going by the manual would be dimm a2 and dimm b2 which would not be a channel if you see wat i mean

i am really confused by this so if some could help me out id be so gratefull.

Your RAM is installed correctly if both modules are installed to either both blue slots (A1 and B1) or the black slots (A2 and B2). Since A1 and A2 are channel A, and B1 and B2 are channel B... for a dual channel configuration, the modules need to be installed in a "1 stick per channel" config. like I noted above. And after making any RAM related changes in the BIOS, instead of trying to boot directly into the OS, boot to Memtest86+ first to check for stability. And you might also want to post a direct link to your specific RAM, or post a pic. of CPU-Z open to the SPD tab showing SPD / EPP timings at 1066MHz.