It is T2 Dispatch in your memory tweaking section of your BIOS. Check my sig, or let me know if you have any questions.
Edit: Well, I just tried changing mine to confirm, but mine stays at 2T. I'm guessing that when set to auto, it may change to 1T if the timings are right and relaxed. Disable prolly keeps it set to 2T at all times.
With high frequency RAM, it is hard for the command rate to be at 1T (I can't remember the exact reason right now, I know it has something to do with the speed, but it's been a while), that is why there is so little talk about command rate these days as opposed to the DDR1 days.
Edit again: Here is a quick google on DDR2 command rate.
It appears it is chipset dependent, and unlikely at or above DDR800.
Here is another describing how it is hard to hit 1T at 800 or above