> It is actually running at 13,3 Mhz now

If you want your PIC running its fastest and comming with a PC,
use a 9.8304MHz and PLL -> 39.321600MHz

If you choose a frequency that's "decimal", eg 40.000000MHz,
then you will have an error at baud rates which are more suited
to hexadecimal timing

eg 40000000 / 9600 = 4166.66667 (h1046, d0.66667 is lost)

but 39321600 / 9600 = 4096  (or h258000 / h2580 = h1000),
which is 0% error (try those figures in the UART calcs)

In this case, 40MHz will be 1.7% high, ie sampling too fast. On
a few bytes, you could work out how many, this probably wouldn't
be a problem, but the PC and PIC will drift apart on longer strings
without a periodic re-synch

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