🚀 go-pugleaf

Roger Walker <rwalker@bourbon> writes:
>The best way to speed up an intel 80486-100DX4 is to find the clock
>DOUBLING pin, shorting this high/low causes the CPU to either
>clock triple or clock double the incomming clock.

Finally - someone who knows what they are talking about.
According to my reference, tying that pin to another signal (cannot remember
which one) switches the chip into 2.5x mode [not sure what that would be useful
for].

>If your motherboard
>is designed to handle 50MHz which some are then set the clock jumpers
>for 50MHz and the CPU jumper to clock double to give you a within
>tolerance (and design specification) 80486-100DX2.  Although the
>CPU throughput is no faster the memory bandwidth (and how fast the
>on chip cache can be loaded) is significantly faster.

The disadvantage is that (for my motherboard at least) is that going from 25/33
to 40/50 MHz I need to increase all the wait states by one. I am not sure if
the slow down this causes would outweigh the speed up of 33->50 MHz local bus
speed.

>Also if you're buying a DX4 CPU think hard about paying the extra for
>the intel part as it has 16K of on chip cache where the others only
>have 8K.

It also has a faster integer multiply (than the DX or DX2 parts).
-- 
David Wilson	Dept CompSci Uni Wollongong Australia	david@cs.uow.edu.au