hrmmm. Sorry, it's a bit of slang or vernacular related to the memory "strap" or divider. You can run your memory in a 1:1 ratio with your "Bus"or FSB. I'm not too sure what you're familiar terms would be. Anyways, when you over clock your FSB to push your processor to a higher frequency(overclock) you can sometimes run the FSB HIGHER than the speeds your memory can handle.
At this point you would want to change the "strap" or divider for your memory. You can run it 1:1, 1:2, 4:5...etc.
So if your FSB is at 800MHz and you want a 1:1 ratio then your RAM must be set to 400MHz. If you want 1:2 then set your RAM to 200MHz. Technically speaking, DDR2 sends data on the rising edge and falling edge of a cycle, therefore it's called DDR2. That means DDR2@400MHz responds in the same manner as DDR@800MHz.
The point of this, when read your memory speed in the 680i bios it will not read in MHz. It will just say "800" instead of "400MHz". So, when looking at your bios you want to be sure that whatever settings you change...RAM Speed ends up at "800". THAT is your goal.
But, to be sure that your memory is stable you want to loosen the "timings" to 6-6-6 at T2 and push the RAM to it's highest rated Voltage, which is 2.1V
Once you can assure me that your RAM speed is 800, timings at 6-6-6 @ T2 w/2.1V and your system is still giving you a blue screen...one of two things could be happening.
A) Because of poor initial setup when installing RAM, data on your hard drive could be corrupt and a fresh install is in order.
B) Your RAM is still unstable and you will need to RMA.
The easy way to end up at (B) without the hassle of (A)? ... Put memtest86 onto a bootable device, i.g. CD-ROM, bootable flash drive, floppy disk, etc., and find out if your memory is performing within acceptable constraints. If it fails, RMA