By default X58 and i7 920 run memory at 1066mhz. You'll need to go into the BIOS and change the default memory multiplier from 2:8 to 2:10, that should equal to 133mhz x 10 = 1333mhz RAM.
As for the rated speed: The SPD chip on your RAM provides a number of potential settings, and your computer's Bios has chosen the default. If you don't like that it's showing a different number, then set your memory divider appropriately. 2:10, as Flyin indicates.
As for any difference in speed... You may not want to bother, since there is little/no performance gain associated by running higher clocks:
------------------------------Which Chip? Well, it depends on which set of thieving b@stardz you choose to support: The ones who use insider trading to enrich themselves while running their company into the ground, or the ones who illegally pay vendors to not support the first group.
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