> squeeze some more speed out

PS, kids, you CAN try this at home

Caution - dirty word follows

Over-clocking

40MHz is not necessarily the maximum speed of a 40MHz part. It
is the maximum speed Microchip guarantees for correct operation

However, you might find that 4x PLL > 10MHz crystal will run OK
(define 'OK' for yourself). By accident I have made an 18F452 run
at 78.643MHz. Happened when I mistakenly used a 19.6608MHz
crystal with a PIC set up for 4x PLL and 9.8304MHz

I did a few checks and this PIC did pass timing tests, didn't get hot
or throw any sort of hissy fit. I didn't try every module though to see
if absolutely everything was still working and working correctly

There is no telling what would have happened or failed eventually with
such a massive over-clocking and it's certainly something I would not
dream of or recommend doing for production. For a personal project
you might get away with a slight over-clocking, say 11.092MHz or 
12MHz crystal

But you didn't hear it from me, right ?

wbr
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