Serial versus PCi modem

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Recently acquired a v.92 internal modem and had assumed that it should be faster than my old serial modem; but not so. My connection to AOL gives the speed (at least of the initial connection). It’s usually about 49,333 with my old modem. Using the manufacturer’s (unsigned) XP v.90 drivers, the PCI modem gets 45,333 at best, usually 36,333. On top of this, the driver has to be uninstalled and reinstalled after every reboot, or AOL hangs in the sign-on process (requiring the reset button).

The supplied v.92 drivers were no better. An Intel signed v.92 driver (modem is Ambient, made by Mentor – a.k.a. Linden-Computech) produced a connection speed of 31,200, at which point I reverted to my old modem . This gives me no trouble, but surely ehe internal modem should be faster – shouldn’t it? Anyone?

I anticipate a barrage of blaming AOL , but why only this modem?

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I think there is some firmware on the modem that decides, during the initial handshake, when a line is too “noisy” for its tolerances at its maximum speed, and progressively drops back to lower and lower speeds until it is satisfied. Whether this determination is being made accurately by either product, who knows, but that is my best guess as to the reason for the difference. Would be interesting to test the two products and see if there was any actual difference in throughput.

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Not sure how to go about comparing the actual performance once online, but the external modem certainly establishes the connection significantly faster. It even dials quicker!

To be honest, my main reason for buying the new modem was for the bundled fax/voicemail software, as the software I had was written for ’95. I think it’s safe to say that any software that loads off two floppies is likely to have a compatibility problem with XP. Unfortunately, it may have XP drivers (which seem to have a problem with AOL), but the software isn’t compatible! Not my best purchase, then.

In principle,though, am I correct in thinking that an internal PCI device should be quicker than an external serial device? I suspect that the difference probably wouldn’t show up with the data flow from a 56k dial-up, or am I wrong there?

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Your internal modem is not set up properly. If the external model dials faster you need to add a setting for your card.

Try this : find your ‘Extra Initiaization Commands’ line. This varies with your OS, but starts : Control Panel/ Modem/ Properties /Advanced – or similar. It’s a line you can type in, so type :
s11=50 .

This will accelerate your dialling to new heights.

btw, I’m assuming you are aware of the difference, when speeds are being bandied about, between that at which your modem talks to your system, and downloading rate. Two entirely different piscine storage vessels. Your 49,000 odd sounds to me like Kbps, which has nothing to do with the rate at which you can get info into/out of your computer.

Rgds

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Sorry, missed this reply for ages. Will give it a try.

Also owe you a response from last year (!), re scanner attachment. I suspect that the transparency device I have will only work with the Agfa scanner, but as I still haven’t used it, it is still looking for a new home. I am moving to the Tunbridge Wells area in about two weeks, so if you want to meet up and see if it is any use to you, let me know.

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In principle,though, am I correct in thinking that an internal PCI device should be quicker than an external serial device? I suspect that the difference probably wouldn’t show up with the data flow from a 56k dial-up, or am I wrong there?

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[/indent]I believe serial ports top out at 115,000 bps, while PCI devices are rated in MHz (bus speed). While I am sure the latter has a great deal more capacity, I don’t know how to compare them directly, and at phone line speeds, I don’t think you would notice a difference.

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To offer another slant on the situation, a little while ago I was in the online backup business. Those in the business from all around the globe swore by good external modems rather than internals. They seem – no scientific evidence that I can quote here I’m afraid – from experience to be more robust and often quicker in transmission and receipt of data packets. As Keith said the pc needs to do less work with an external, meaning that the end result is quicker transmission. My

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Thanks to everyone for the input. Been away from home for a while, so just had a chance to look at everything.

Don’t think that the demands of a modem on 1800XP with 256MB RAM should be too much for the system to handle, with not much else going on when I go online. Maybe the serial modem, despite it’s age, is just the better piece of kit. Hard to verify speeds, apart from how long it takes to get online, which is noticeably faster.

Have added command suggested by Mercury, but will wait to try it out tomorrow (Boing, time for bed , said Zebedee).

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PCI modems are generally “Win modems”, that is they do not have all of the hardware a serial modem has and a lot of the work is carried out by the PC itself.

Check out: http://modemsite.com/56k/index.asp%5B/url%5D for an excellent source of information.

Oh dear. Just checked out the site. A lot of the content is now only available if you pay a subscription. I suppose that’s fair enough as the owner must make a living but what irked me was the discussion board is also pay only.

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Sorry Keith but there seems to be a bit of a misapprehension here. A Winmodem is a software implementation of the idea, with minimal hardware (controllerless) using, as you say, the system’s internal resources/hardware and is generally of very limited value in a desktop machine.
As far as I am aware, what is meant by a ‘PCI modem’ is a card that fits in a PCI (as distinct from the old ISA) slot on your motherboard. As such it is hardware and should have its own controller chip and so on. It is a perfectly repectable (esp. if it’s a v92) 56Kb modem – they don’t come much better at the price. Maybe the terminology is different down there. Have a look here

Rgds

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Yes, you are right, “PCI” is how the card interfaces with the PC and “Wimodem” is how it works but, from my reading, most PCI modems are Winmodems. The following are but two sites which state this (the first being from the same source you quoted ):
http://www.56k.com/links/Specialty_Modems/PCI_Modems/%5B/url%5D
http://www.pcworld.com/resource/article.asp?aid=9350&pg=2%5B/url%5D

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