1.9) Let's suppose we have a 40-year-old computer that has an instruction execution rate of one thousand instructions per second. How long would it take in days, hours, and minutes to execute the same
number of instructions you derived for the 500 MHz machine? [It worked out to 30 billion instructions a minute.]
1.9) This computer only runs at one instruction per millisecond, which is a thousand microseconds. Thus it is only getting sixty thousand instructions out in the time it would take our other computer to do thirty billion.
Thus, for our forty year old computer to get thirty billion instructions done, it is necesary for it to take 500,000 minutes.
There are 60 minutes in an hour. It would take 8333 1/3 hours to do those instructions.
There are 24 hours in a day. It would take 347.2 days to do all those instructions on our forty year old computer.
So, assuming you started at midnight of a new non leap year, and just kept running, at 5:20 AM on December 13th, your old computer will have processed thirty billion calculations. I'd say that's a good enough reason to upgrade.