🚀 go-pugleaf

asti...@csd4.csd.uwm.edu (Anthony J Stieber):
> In article <1990Feb28.1...@larry.mcrcim.mcgill.edu> pani...@Moe.McRCIM.McGill.EDU (Jean-Francois Panisset) writes:
>>...no way you can make a computer run 3 times faster
>>without spending major bucks :-(.
> 
> Not strictly true.  A common modification on the old IBM PCs is
> to replace the 8088 with a NEC V-20 or similar ship and the crystal
> with a faster one.  Thus a 4.77MHz machine might clock up to 8Mhz or
> more instead.  This modification costs about $20.  
> 
Well... This doesn't always completely work....  Sure, you can replace an
existing processor and crystal with a faster combination, but all you are
doing is increasing the speed of the bus clock, which can cause more
problems.  If the rest of the circuitry (logic, memory, etc.) in the computer
can't handle the faster speed, the processor will end up sitting
idle waiting on the rest of the computer.  (At the very least...)
In fact, this can make the machine run even slower than before the 
modification...

> A 386sx motherboard costing $300 for my $1600 (in 1987) clone will
> boast it's present speed about ten times.

This is really the only way to make sure that you are truely increasing
the speed of the machine.  Make sure the whole board is designed for 
speed in mind.  The processor is not the only thing that uses the bus 
clock...   Much of the circuitry around the processor is also synchronous 
(containing flip-flops, latches, etc.), meaning that it also depends on 
the clock.   If the clock is faster than the original engineers intended, 
timing errors may result, and nobody knows what can happen next....

pjz...

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