"LASERandDVDfan" bravely wrote to "All" (15 May 04 23:37:46)
--- on the heady topic of " PSU Fan Direction"

LA From: (LASERandDVDfan)

LA What a modem essentially does is MOdulate the information to be sent
LA into a simple analogue carrier that can be transmitted through the
LA phone lines. The computer that receives this signal DEModulates it
LA from an analogue carrier back into usable computer information. It
LA modulates the information to be sent into a simpler form and then
LA demodulates information it receives back into something that can be
LA processed, hence the name (MOdulator DEModulator or MODEM for short).

Modems do a lot more than make sqweeks and squawks into the phone
line. They compress the data and send it as packets with error
correction. Then the receiving end receives them and decompresses the
data. All the while both ends are monitoring line quality and
negotiating the next transmission. Where a softmodem falls short is in
the lack of its own cpu and a software driver must hog the main cpu to
emulate the modem's cpu. In a very powerful pc this isn't usually too
bad but in general mostly all other running programs suffer.

The easiest analogy of this is an audio soundcard where the
instruments use emulated wavetable synthesis to drive the D/A
channels. Usually these drivers will emulate some synthesizer, like a
Yamaha etc. This works pretty well most of the time but when the
system starts running out of resources, the synthesizer starts to lose
instruments, go out of tune, or do other weird sounding things.

No software can beat a hardware system. Especially not a winmodem.

Asimov
******

.... A fail-safe circuit will destroy others.