Will an increase in clock speed show up in the current-drain of any of the low-power modes?

[lpcware-support]

For sleep mode, you will see a difference in current when changing the frequency. The peripherals can be powered off for lower consumption. The peripheral power consumption data can be found in the device datasheets.

In deep sleep, power-down and deep power-down modes, the frequency don’t affect these modes since the clocks are shut-off in the LPC17xx.