The CPU in the Nook Color is a ARM Cortex-A8. CyanogenMod 10.1 can be installed easily to the EMMC on the Nook Color. By default, CyanogenMod 10.1 runs the A8 at a maximum frequency of 800MHz. But, it has been found that the A8 on the Nook Color can be safely overclocked up to 1100MHz. This can be reduce some of the lagginess in CM10.1 and help during video playback or other CPU-intensive operations.
Overclocking the Nook Color is pretty easy:
Enable Developer Options and Performance in the Settings application.
Go to Settings > Performance > Processor. Change the Maximum CPU frequency from 800MHz to any value, including 1100MHz. Enable the Set on Boot option so that the CPU is always overclocked. Done!