h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

In actuality, depending on the modem, and exrtra 50 MHz clock speed CAN make your modem faster. These modems are typically known as win-modems, though they are also called HSP Modems, HCF Modems, Soft-Modems, and other non-obvious terms. The reason these modems can work faster depending on your CPU is that they do not (as opposed to a full blown hardware modem) have all the hardware necessary for the modulation and demodulation of analog data signals built onto them. Instead they rely on the computers own processor and ram to do that for them, the lazy buggers. Utilizing modem initialization strings, you can tell the modem to use X amount of the CPU's Processor to modulate and demodulate analog data signals, thus speeding up a modem with that extra 50 MHtz Clock speed.

Almost true... except it's not the modulation/demodulation that's processor dependent, but rather the data compression. Any modem over 19200 Baud relies on some form of compression to squeeze the data stream into the available bandwidth. Fast external modems have their own RISC processor and flash ROM to handle the compression algorithms, and hence cost more than WinModem devices which rely on your CPU to do the hard work. (This is why most 33.6K Modems can be "flash upgraded" to whatever the current standard is, usually at no cost to the user! The modulation/demodulation hardware hasn't changed in five years, only the compression algorithms have improved...)

The downside of these "WinModem" devices is that they need a minimum guaranteed CPU speed to be able to keep up with the data stream, and so won't work on most 386s, 486s or even slow Pentiums (sub-166MHz). Also, because they need Windows drivers to run, they are generally useless in DOS, CPM/86, Linux, OS/2 or BeOS.

broadband is a far better way of improving your internet connection speed than getting an extra 50Mhz clock speed. And the difference is so small it really is pointless

I managed to jump from around 33 to 49K, which was noticably faster. It's handy if you don't have broadband, but it's not worth the cost of a new processor. A nice bonus if you happen to be upgrading anyway, though.