Your math is two digits off. Using Grace Hopper's "one nanosecond is one foot", one cycle at 10 GHz is 1/10 of a foot or 3 cm. That's 30,000 microns not 300.

Your math is two digits off. Using Grace Hopper's "one nanosecond is one foot", one cycle at 10 GHz is 1/10 of a foot or 3 cm. That's 30,000 microns not 300. But yes, the speed of light limitation on signal propagation is a major factor in our current limit of 3 to 4 GHz chips.