54xx/55xx/64xx/65xx/TAM G3 Upgrades Why No 300Mhz Cards?
Q:Why doesn't Vimage offer a 300-MHz card for the machines mentioned in the title?
A: The cooling requirements of the x4xx/x5xx are such that a silicon-300 MHz CPU (without a fan) will run hotter than the machine can comfortably tolerate. This especially holds true for the Twentieth Anniversary Mac, whose internal design makes even a 240-MHz silicon chip inappropriate
By using too hot a CPU, you may upgrade your computer's performance in the short term; but, as the weeks and months go by, you can expect to find your machine's health in increasingly sharp decline.
Although somewhat more expensive, a copper CPU will run much cooler, and not cause long-term damage to your computer that may not be apparent over the first couple of weeks or months of use.
The market right now is such that copper CPU upgrade cards are somewhat over a thousand dollars. It is extremely likely that anyone who tries selling you a "much cheaper card that is made of copper" is either (better case) misinformed, or (worse case) being "economical" with the truth.
With technology, perhaps more than most other things, you really do get what you pay for.
See the 54xx/55xx/64xx/65xx/TAM G3 upgrade FAQ for more information
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