Internal -vs- External modem

[w_tom]

Your modem selection is based upon many factors. But the
one based upon surges is not valid. Understood why the Belkin
can even contribute to modem damage. The surge, shunted to
close to computer onto all other wires, simply is given more
potentially destructive paths to earth ground. Belkin can
complete a destructive circuit path through modem even when
computer and modem are powered off.

Described is a surge protector that is useless because it
does not shunt a surge to earth ground. In your case, Belkin
would shunt the surge, destructively through modem - internal
or external. Power on or off would not matter since the
adjacent surge protector still would shunt a destructive surge
to earth ground via that modem.

Three reasons for using an external are 1) a modem that can
quickly be moved to another system, 2) a modem that will work
on any operating system, and 3) a computer CPU less than 200
Mhz. Other reasons, such as reliably, are not a function of
internal verses external. Reliability is mostly a function of
someone using cost controls to buy the modem.

 

[@drian]

...2) a modem that will work

on any operating system

Wouldn't an internal version work on any operating system, with it being
PCI? Or do you mean you can take the modem and plug it into a Sun Blade and
it works?

Other reasons, such as reliably, are not a function of
internal verses external. Reliability is mostly a function of
someone using cost controls to buy the modem.

Reliability or should I say compatibility is a factor, as some motherboards
don't allow some internal modems to work correctly. I've read as such on
past postings on newsgroups, in addition to experiencing this myself. I've
never heard of an external modem via a COM port and serial cable not
working.

@drian.

 

[w_tom]

Hardware modems have the computer onboard. Winmodems
instead use the main CPU (and drivers in the Operating
System). This makes Winmodems less expensive AND is why they
must run on systems faster than 166 Mhz. Software modem
requires drivers written for that operating system and not
just a serial port interface driver.

The only reason I have seen an internal modem fail is due to
installation in violation of specs OR some clone
motherboards. If having done hardware design, then timing
conflicts and even metastable state problems are appreciated.
Just because one PCI card works on the bus does not mean all
will do so. PCI bus or PCI interface on card can have 'hairy
edge' timing problems. These occur more frequently when price
rather than value is why a modem is purchased. Those other
modems cost more because they did more to avoid that 'hairy
edge' problem.

I have seen external modems not work right. But since then,
external modems are no longer sold by those selling to 'cost
control' mentalities. External modems cost more meaning that
cost control mentalities and their manufacturers will flock to
internal modems. Problem is not the internal modem. Problem
is the top management of some manufacturers and their
customers - best described as a bean counter mentality - who
give internal modems a bad name because they don't buy or
design using value.

Avoid the cheap clone internals and you should have no
internal modem problems. If a brand name internal modem does
not work, then suspect a motherboard problem. Technology is
that well proven.

 

[William]

Excuse my comment on surges as a comment in the selection of a modem. If
you have the outlets available, and the serial cable available, it would
be most beneficial to purchase an external modem. You will have to
sacrifice a serial port, but it will be well worth it. I do have to
comment that the internal modems I have used in the past have worked well,
except for the lucent technologies winmodem that I had to work with a bit
to work. It was not alot of trouble to get working, just a few extra steps
to get going. The external was a quite a bit easier to get going. Shall
your endeavor help you greatly.

 

[alvin york]

Hi Adrian!

Thanks for the link Rich. After reading it all, I don't feel I'm any
better off knowledge-wise, as some people say it works (the internal
version), some say they have problems.

Looks like further research is required.

@drian.

Adrian, internal modems work just fine if you set them up properly.

When I install an internal modem, I go into CMOS and Disable Com2.

Modem is then usually installed by Plug n Play Setup on Com2, and uses
either IRQ3 or IRQ4, I forget which. Sometimes it takes IRQ10 as does the
modem I am now using.

Regardless internal modems work fine and save desk space.