[BeagleBoard-xm] Why the MIPS of the arm core only 594?

Hi all
I bought a beagleboard-xm, the Serial number is 1151xM797. I run andriod 2.3 , the context of /proc/cpuinfo is :
Processor : ARMv7 Processor rev 2 (v7l)
BogoMIPS : 597.64
Features : swp half thumb fastmult vfp edsp thumbee neon vfpv3
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x3
CPU part : 0xc08
CPU revision : 2
Hardware : OMAP3 Beagle Board
Revision : 0020
Serial : 0000000000000000

From http://en.wikipedia.org/wiki/BogoMips:

" "Bogo" comes from "bogus", i.e, something which is a fake. Hence, the BogoMips value gives some indication of the processor speed, but it is way too unscientific to be called anything but BogoMips.
The reasons (there are two) it is printed during boot-up is that a) it is slightly useful for debugging and for checking that the computers caches and turbo button work, and b) Linus loves to chuckle when he sees confused people on the news."

Hi everyone,

BogoMIPS : 597.64

There is additional problem in recent kernels around BogoMIPS. The
calculation of BogoMIPS occurs quite early in the kernel
initialization. If you supplied the "mpurate=800" or something like
that to kernel, then it switches to the new frequency, but it doesn't
recalculate BogoMIPS (which was the case with old, pre 3.0, kernels).
This means, that BogoMIPS corresponds to frequency initialized by
u-boot, which is set to safe 600 MHz (hence BogoMIPS ~ 600).

BTW, maybe it's good idea to switch CPU in u-boot to higher frequency,
we do know in u-boot model of the CPU ?

Hope this helps,