This is - Helping you get the best performance from your modem
 Troubleshooting News Technical Search
 Home Forum 56 Premium Site Map
Home Troubleshooting    LT Win Modem    Compaq Supplied Modem    Compaq & LT

Compaq System w/ LT Modem (Updated 17-Jun-00)

Note: Compaq has released a V.90 upgrade for a number of Presario models that came with a KFlex LT Win Modem. These notes apply to using "generic" firmware. Check the LT Firmware list for a link to the Compaq V.90 Softpack.

While I don't have any personal experience with a Compaq system, I've heard from a number of Compaq users that have successfully upgraded their Compaq modem with Lucent chipset to gain V.90 capability.

As I understand, Compaq has 2 models of modems based upon the Lucent Apollo/Mars chipset (LT Win Modem): the 56k-DF and the k56-VSC modem. The first has only data and fax capabilities, and there should be no loss of functionality in upgrading the modem. The VSC (voice) modem is another story - when upgraded to V.90 with the Lucent firmware available here, you will lose voice (ie Compaq PhoneCenter) capabilities, and you will also lose modem audio when you dial out, and so far, I've not heard of anyone avoiding this loss with the VSC.

Compaq's LT modem with Compaq-supplied KFlex driver does not identify itself as a "LT Win Modem". However, the Lucent-supplied 5.32 driver that you can download from my site can be used to update the Compaq modem:

From Kelly Johnson:
I downloaded the full zipped 5.32 version and ran setup on a Compaq 4532 with the 56K-DF lucent based modem and also on a 5036 Compaq with an ActionTec 56K-V90 voice modem. Both installs went without a hitch. The Compaq modem is now reported as an LT (which it is huh) I get 50,000 Flex connections and 49,333 to 50,666 V90. I even tried to mess up the install on the Compaq modem (deleted various files first) and the install went fine. Just a FYI and keep up the fine job your doing.

From Gary in Boston:
I found you site becuase Compaq is telling people that although they will not (apparently never) help them upgrade (or at least until next year), they could try copying the Ltmodem.vxd file from here. I have a 4814.

I did this and did connect at 50k. I think I was using V.90, but have no way to confirm it; Compaq completely hides all access to the modem string.

The problem I had was that when I made the change, all audio was disabled from the modem (it's a voice/fax/data unit.)

I searched for Ltmodem.inf and found that there is no such file in my computer.

So until Compaq decides to get off thier greedy backsides and help-out the owners of these heaps of junk I guess we're stuck with k56Flex.

Notes to Gary: 50k is NOT a V.90 rate - 50k (as well as 34k, 38k, 42k, 46k and 54k) is a Flex-only rate. I'm not sure, but the first message indicates no problem running the 5.32 install on a Compaq, where Gary indicates he only copied the .vxd.   In any event, it might be better to run the Lucent-supplied 5.32 setup (modem532.exe) program. The Compaq support forum has a FAQ for the 4600 series that discusses the V.90 upgrade; you must register as a user at, then select Presario Msg Board 1; then the 4600 series from the drop-down menu, which will take you to the 4600 FAQ which includes: 2.) Modem upgrades to V.90

Lisa J.  was successful at updating her Compaq modem and keeping her modem audio with the following procedure:

Just installed the 5.32 version on my Compaq 4862. I ran the full setup app and had the same problem as Gary did but believe this work around will solve it. (P.S. I'm running Win98) First, do the Find on 'serwave.vxd' and note the location. Then go into Control Panel...Add New Hardware applet, let it find that the Voice for Modem Wave (oops, name might not be right) isn't installed (it should have a yellow exclamation point over the device). When it asks where is the best place to find the driver, point it to the location that you noted above and press OK. Everything should work after a reboot. Anyway, I now have connect speeds of 46,666 with the forced V90 which beats the you-know-what with the 24,600-26600 I was getting before. Thank you SO MUCH for the information!

Kelly J. has the add'l info related to Gary's problem:
In response to Gary's Compaq 56K-DF. The inf. in the Compaq are not named LT, they are under where the x's may be 97, 17, 18 ect. Prior to the 5.32 versions the only way I could get V90 was to delete the hkr. responses from the original inf. and insert the hkr.responses from the new V90inf. I have been getting V90 connections for months. As I stated before I ran the full 5.32 zip and had no trouble with any Lucent based modem. I have now run the 5.32 on 5 different systems and have not had any "sound" problems. The Compaq 56K-DF is not voice capable anyway.

Summary - VSC (voice) modem:

You will lose sound of modem dialing and the voice features of the modem with the Lucent V.90 upgrade. You can switch back to the original Compaq-supplied driver to re-gain the voice capabilities. To switch back permanently, uninstall the LT Winmodem (5.32 drivers) and reinstall the Compaq supplied driver. You may also be able to switch back and forth between the 5.32 V.90 and original Compaq drivers without uninstall/reinstall by following this procedure tested for me by 4814-owner Leroy:

Upgrade the VSC modem to V.90 using the full 5.32 Lucent setup. Uninstall the LT; re-install the Compaq drivers. Now, you should be able to copy only the ltmodem.vxd file from 5.32 and the modem should work (you may need to add s38=0 to extra settings to get V.90 connects to some servers); however, handshake sound and voice capabilities will not work; when you want voice capabilities back, replace only the ltmodem.vxd file with the original Compaq-supplied ltmodem.vxd; you should get handshake sound and voice capabilities back, however, with the PhoneCenter, Leroy would get an error in loading the TAPI file (something to do with functioning of the fax operation?) AND upon closing the PhoneCenter it would take a long time to close and then would get an "Error in Closing FAPI 01Driver" message.

Windows 2000: Problems with the proprietary nature of Compaq systems prevent using most Compaq systems with LT modem with Windows 2000. A Compaq user in Virginia filed a complaint with the Texas Attorney General regarding his Compaq system and received this reply from Compaq:

This letter is in response to your complaint filed with the Office of the Attorney General, State of Texas regarding your Compaq Presario 1236 laptop computer purchased January 1999 with Compaq 1-year Limited Warranty through January 2000. Please note the Compaq 1-year Limited Hardware Warranty is expired on your computer.

Compaq regrets to learn of your misunderstanding regarding the functionality of the BIOS in your Presario model 1236 computer. Your perception of a manufacturing defect with the BIOS is misinformed.

The Compaq Presario model computer line was designed for the Microsoft Windows 95 Operating System or the Microsoft Windows 98 Operating System, depending on the year the computer was manufactured. We have never supported the Microsoft Windows NT Operating System on any Compaq Presario model computer. Compaq has never advertised or marketed that Microsoft Windows NT Operating System would function on our Presario model computers. In addition there is no Presario model computer listed on Microsoft's Windows NT Hardware Compatibility List (HCL). Effective February 2000 we began supporting the Microsoft Windows 2000 Operating System on specific Presario 1800 models only. Therefore we do not have and cannot provide drivers for the Microsoft Windows NT Operating System nor for the Microsoft Windows 2000 Operating System on Presario laptop model computers other than the specific Presario 1800 models manufactured after February 2000.

The Compaq Presario model 1236 laptop computer that you purchased was specifically designed to run the Microsoft Windows 98 Operating System. The BIOS issue that interferes with Microsoft Windows NT and Microsoft Windows 2000 operation of the modem does not affect the unit and its designed and warranted configuration.

Compaq does not recommend the use of non-supported operating systems on this computer as the computer may not function as designed. Other examples of non-supported Operating Systems would be the Macintosh Operating System, the Linux Operating System or the BeOS. Furthermore the WIN modem in your Presario model 1236 computer is not designed to function in the absence of the Microsoft Windows 95 or the Microsoft Windows 98 Operating System.

Compaq Computer Corporation strives for the highest level of customer satisfaction and product support. I hope that the explanation above responds fully to your concerns.

Very truly yours,

Jan H. Smith
Consumer Customer Service and Support
Assistant Legal Liaison Executive VIP Team

Robert in Orlando sent in this feedback to 56k=v.Unreliable:

It seems that Mr. Jan H. Smith did not do his home work when he said that the 1236 Presario is not on Microsoft compatibility list. Not only was the 1236 on the list but the whole 1200 series. This message is for you Mr. Jan H. Smith, your are a company man! Do your homework. If Microsoft says this machine is capable all you have to do is have the drivers updated and stop waisting Compaq's money and frustrating customers and do your job; support the customer and stop excusing the company and playing litigation games. The 1200 series is very capable about running Windows 2000 and you know it. Get with the programming Mr. Consumer-Customer-Service-and-Support-Assistant-Legal-Liaison-Executive-VIP-Team-Man.

"In addition there is no Presario model computer listed on Microsoft's Windows NT Hardware Compatibility List (HCL)." Cut the Bull! or get a bad reputation, got it.

This lists all the compatible Presario models that are compatible with Microsoft 2000 Professional, they are listed in the HCL.TXT:

Compaq Presario 1234
Compaq Presario 1235
Compaq Presario 1236
Compaq Presario 1237
Compaq Presario 1245
Compaq Presario 1246
Compaq Presario 1247
Compaq Presario 1250
Compaq Presario 1252
Compaq Presario 1255
Compaq Presario 1257

Home  |  Links  |  Send Feedback  |  Privacy Policy  | Report Broken Link
Legal Page  |  Author's Web Sites   |  Log In 1998-2022 v.Richard Gamberg. All rights reserved.