Underclocking has advantages too!
Underclocking by using SLOWER crystal can significantly increase the lifetime and durability of your CPU. The last time I bought a computer the technician tried to tell me this is impossible -t'aint it's simple. Just use a slower crystal.
The reasons are simple too:
1.Heat Kills.
2.Chips are made on very large wafers.
1.HEAT - If technical makes your eyes glassy skip this.
The main source of heat on a chip fabricated by CMOS technology (every chip in our computers) is capacitive dissippation - the energy lost as the junctions in the devices on the chip turn on and off. This heat energy rises as the SQUARE of the operating frequency. (This is why TTL is more energy efficient above 4MHZ (not GHZ) than CMOS. I can post on why CMOS is just about the only chip technology if anyone cares.) Anyhow, If you are running at say 2.8 GHZ you will generate 25% less heat than you would at 3.2GHZ. This really makes a difference. The rule of thumb is an eight fold decrease in component life every time the temperature doubles.
2.Big Wafers. The wafers the chips are cut from contain thousands of devices. Unfortunately we are working at feature sizes less than a wavelength of light in an imperfect world. That means that even though the chips all saw exactly the same process they are NOT all the same. Throw in the inevitable variation from wafer to wafer and day to day and they are really not. So the chip maker uses a very expensive (Last one I bought cost $17megabucks and that was nearly ten years ago.) to test and mark every chip. The price premium for fast operation makes the expense very worthwhile. BUT, that means that when you buy a chip that is rated lower than the top premium speed that the maker offers, it FAILED to meet the criteria for top of the line. I'm going to skip talking about a lot of stuff here. The failure to meet top line specs doesn't mean it's a bad chip, but most of the failure mechanism are accelerated a higher temperatures, and the lower rating may well have come from the presence of a defect such as a slightly thinner oxide layer which would be affected by higher temperatures.
I'm a real cheapskate so I tend to buy well below the top speed. But if I look at the incremental cost of the next higher speed CPU it's cheap insurance to clock it down, since then I know the chip I've bought passed a test for a higher speed and thus the failure rate at the lower speed will be lower by the SQUARE of the difference in speeds.
Re: Underclocking has advantages too!
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