EDIT: ...... And post #10 doesnt say anything about setting it to 1066...
Mate, it's there in the picture, why would you bother buying 1066MHz memory to run it at 800MHz??.
What the DRAM Ratio in the picture refers to is the percentage of the FSB the memory runs at using that strap/divider, e.g. 333/1066 (5:8) could be written as 1:1.6, FSB 333*1.6 = 533 which with Double Data Rate equates to 1066, the 333/800 strap can be written as 1:1.2 etc etc
You can make an auto calculation table in Excel to see different settings such as
(375*1.6)*2 (333/1066 strap) which will give you 1200MHz memory speed or
(375*1.2)*2 (333/800 strap) which will give you 900MHz memory speed or
(400*1.2)*2 (333/800 strap) which will give you 960MHz memory speed or
(450*1.2)*2 (333/800 strap) which will give you 1080MHz memory speed
(I'm not sure if your Quad would run at 450MHz FSB, give it a try and see as 450*6.5 will give you 2.925GHz and your memory "should" handle the mild oc from 1066 to 1080, you may need to loosen the timings 1T to 2T most likely or 6-6-6-18 though I doubt you'll need to do the latter)
Here is a pic of the one I use for my Black Ops, by changing the FSB or multiplier value it automatically calculates the cpu speed and memory speed for the given multi/dividers (straps)
You will be limited to which straps you can use with your FSB over 333MHz by your memory as it is obviously not going to do 1200MHz, though as I said earlier you don't really have a large selection to choose from. I'd be trying them all (the relevant ones anyway) because I had an Asus board once that had an awesome 200/*** strap whereas the 333/*** - 400/*** straps were next to useless
Using the 333/1066 strap your board should run your processor at 2.66 and your memory at 1066.
By using different straps you can run your memory faster than the FSB, or run the memory at default speed while increasing the FSB/CPU speed.
Yes you are right at default I can set it to 333/1066 = 1066MHz (but that is not the default speed, 800 is) but with a 8*375 = 3.0Ghz the 333/1066 = 1280
I don't understand what you are referring to here with the 800? Is it because that is what the board sets the memory to when you leave the frequency on auto? That will be because the memory SPD is programmed to JEDEC standard DDR2 800MHz and will default to this unless you set the correct frequency in the bios using the correct strap, apart from that it has nothing to do with the board and is not a board default.
Data sheet link