Computer C1 has an overall CPI of 2.0 and can be run at a clock rate of 2 GHz. Computer C2 has a CPI of 2.5 and can be run at a clock rate of 3 Ghz. A particular program when compiled for Computer C1 has exactly one million instructions. How many instructions would the program need to have when compiled for Computer C2, in order for the two computers to have exactly the same execution time for this program?