Latest IBM-supplied LT WinModem Drivers

|   Version 5.48 [v.90]    |    Version 5.18 [v.90]    |    Version 4.23 [k56flex]    |
Early on with the first implementation of AT&T;/Lucent WinModems on Aptivas disappointing results were almost universally reported as far as connection speeds. Although the newer IBM Aptiva models had a separate modem and soundcard (and therefore none of the concurrancy issues that plagued the earlier models with the MWAVE card) initially it didn't seem that IBM's switch to the LT WinModem as the modem de jour on it's Aptiva home PCs was much of a step in the right direction.

Fortunately as time marched on and Lucent updated their modem code newer driver releases seem to have helped in many cases.

These files on this page can be used to update Aptiva 2159-S80, 2159-S90, 2161, 2162, 2140, 2142, 2136, 2137, 2138, 2139 and 2153 systems which shipped with the AT&T;/Lucent Technologies WinModem. Note that while these files can be applied to all LT WinModems when applied to early 2159, 2161 and 2162 models which were sold with the first design 33.6k modem which was specified as being non-upgradable to 56k while the drivers may provide better performance they will NOT yield faster than 33.6k connections.

Important Note: While these are the most current IBM-supplied Lucent WinModem drivers there are more current drivers available directly from Lucent which can be used with the modems which shipped OEM on IBM's Aptiva PCs. These drivers can be obtained here:

Latest IBM-supplied V.90 drivers for LT WinModems


1.24MB (1,305,633 bytes)
Released 01/19/2000

  1. Download AA7Z01US.EXE to your hard drive.
  2. Double-Click on the AA7Z01US.EXE file to extract it's contents
  3. Accept the default path of C:\DRIVERS\AA7Z01US
  4. Click Start > Click Run
  5. Type C:\DRIVERS\AA7Z01US\SETUP > Click OK
  6. Follow the prompts and the drivers will be installed
  7. Shut down and restart the PC
  1. Click Start > Point to Settings > Click Control Panel
  2. Double-Click on the Modems icon > Choose the Diagnostics tab
  3. Click the More Info button. You'll find the driver version listed under
    AT15. If the update was successful you should see 5.48 listed there.

Older IBM-supplied V.90 drivers for LT WinModems


2.18MB (2,290,901 bytes)
Released 08/11/98

  1. Create a new folder on Drive C named "518" (C:\518)
  2. Download the file LT518.EXE into the C:\518 folder
  3. Double-Click on the LT518.EXE file to extract it's contents
  4. Click Start > Click Run > Type C:\518\SETUP > Click OK
  5. Follow the prompts and restart the PC when requested

After running the LT518 file your modem will comply with the ITU V.90 specification enacted 2/98. You may experience increased performance from your modem after installing these drivers, however many factors will affect your modem connection speed. IBM has developed a set of Frequently Asked Questions which covers some of the factors involved in obtaining high speed modem connections.


IBM has included the 4.23 level of drivers for the LT WinModem with the 5.18 v.90 drivers so to easily support returning to the previous drivers in the event of any problems. If you wish to return to version 4.23 at any point:
  1. Click Start > Click Run > Type C:\518\EMER.BAT > Click OK
  2. EMER.BAT deletes the 5.18 files, then extracts EMER.EXE
  3. Click Start > Click Run > Type C:\518\SETUP.EXE > Click OK.
Please view the C:\518\README.TXT file for more details
Latest IBM-supplied k56flex drivers for LT WinModems


1.13MB (1,194,519 bytes)
Released 02/11/98

  1. Download LT423.EXE to it's own folder on your hard drive
  2. Double-Click on the LT423.EXE file to extract the contents
  3. Double-Click on the extracted SETUP.EXE file to install the drivers.

These drivers are supplied with the hope that they may help users to obtain connect speeds that a unit sold as a 56k modem should provide. As always your feedback is invited and appreciated.

TO DON5408's

© 2000, Don Schneider aka DON5408
DON5408's Unofficial Aptiva Support Site