RAM gets new identity under speed...

I have 4GB of Ballistix PC8500 1067 ram which the Asus Commando mobo correctly identifies, set with 2.2V at 5-5-5-15. This is fine.

Playing around with the overclocking today, I set the FSB to 400 and the RAM happily at 1200, wherein it ran just fine, with CPUz reporting it at FSB:DRAM 2:3 600, as it should.

Whence rebooting I discovered that the Commando now cares to identify the ram as PC6400, and not as PC8500 which it had before. This isn't really that important, as I can verify it's running at the appropriate speeds...

...but why would the PCxxxx number change?

It happens I guess. My ram is @400mhz - gets reported as PC5300 on post screen.
I have no idea as to reasons behind it, but I believe its to do with the overclocking linked in with your dividers which confuses the mobo.