> I have two PCMCIA modems which I use with my laptop. Both are "56k
> V90" modems, so I would have expected that they would work in similar
> ways. But they don't.
They operate differently -- different software (drivers) and different
mechanics. The only commonality is your O/S and machine.
> The 3Com Megaherz 3CXM756 (which fits discretely into the PC card
> slot) generally connects to my ISP (ntl:freedom) at about 29-36kbps.
> Which is way below what I would like.
(1) You can set the maximal allowed speed under modem properties in
Window$. Beyond this, you will have no control over the speed which is set
at the time of connection.
> The Compaq Compact Flash modem (in CF -> PC card adaptor, which sticks
> out the side of the laptop like a sore thumb) generally connects to
> the same ISP at full speed.
> Drivers for both modems properly installed (in Win XP).
(Maybe obvious, but...) If the drivers weren't installed properly, the
modems would simply not work. Not work _slowly_, but would _not work_.
> Why the discrepancy?
(2) The ISP side can distinguish between the modems. Maybe you have a chance
of improving the speed by changing the initialisation string somehow.
> Is there any way I can boost the performace of the 3Com modem to equal
> that of the CF modem?
Try (1) or (2).
> Or is the 3Com one just crap?
"Less compatible", maybe.
> If that's the case, can anyone recommend a decent PC card modem that
> doesn't stick out of the laptop like a sore thumb?
It's not hard to find, but I can't recommend any.
Hope it helps,