Alan, at 09:39 on Mar 06 1996, you wrote to Bill Grimsley...

ALM> Not that I want to get involved in the modem wars, but you lot did discuss 
ALM> the port speed at one time so I changed mine the other day from 19200 to 
ALM> 32400.

Presumably that's a typo, and you meant 38400.

ALM> Over several days the transfer rate was down by approx 300cps, so I've put 
ALM> it back to 19200 and it's fine again.

Urk!  What's the story with your machine?  Is it an XT or something?  :)

ALM> What's the story with that one?  I always thought that faster was better.

The short story is that with sufficient CPU grunt, your PC should be able
to handle a port speed of 4X your modem's greatest speed (i.e. 57600 for a
14400 modem, 115200 for a 28800 modem, and so on), which allows for the
theoretical maximum data compression of 4:1 provided by BTLZ.  However,
several things can impact upon those higher port speeds, such as lack of
CPU power, multitasking OSs, interrupt latency, write-back caching, and so
on.

Yours is not a typical problem though, and I wonder if the modem and term
have been set up correctly, as even an old 286/10 should be able to handle
a port speed of 38400 without problems (the need for a 16550 UART
notwithstanding).  Be warned also that some apps like Telix MUST have their
dialling directory speeds set to the same as the port rate, or you'll have
problems.

Regards, Bill

--- Msgedsq/2 3.20