Although IBM officially states that you cannot drive a monitor at a resolution greater than 1280x1024 with the DVI output on the optional Port Replicator II docking station, with the ThinkPad T30, it turns out that you can---if you know what to do.

The heart of the problem is that the digital transmitter (TDMS transmitter) in the T30's Radeon 7500 graphics hardware has weak signal strength. In fact, the original DVI specification didn't even provide for resolutions above 1280x1024. As you increase the digital signaling frequency, you decrease the power per bit of information (there is a fixed amount of power, but you send more bits per second). On top of that, add on the additional signal attenuation in the majority of cheap DVI cables at these higher frequencies, and poor quality DVI receivers in monitors, and you have a recipe for disaster.

However, in my tests, I was able to drive a flat panel with 32-bit color at 1920x1200 at 60 Hz with the 2 meter DVI cable included with the monitor, and of course, a short 1 meter high quality DVI cable (Monster Cable DVI400) which I ordered just incase the free cable was insufficient. In fact, I didn't even need to mess with various video tweaking control panels to reduce the DVI frequency by reducing the extra timing information for either cable. With the default options and the ATI Catalyst 6.5 drivers, my Dell 2407FPW 24" LCD panel worked just perfectly at 1920x1200 resolution.

Of course, your results will vary. Possible variables include the quality and length of your cable, the quality of your monitor's TDMS receiver and possibly the revision of your T30 hardware (some users claim the newer T30s use poorer quality TDMS transmitters).

Here is what you need:

• ThinkPad T30 (my version is the early model 2366-44U)
• DVI Cable
  • Typical 2 meter DVI cable. (Use the 1 meter cable listed below if you receive video noise)
  • 1 meter high quality DVI cable (I used the Monster Cable DVI400-1M from Amazon.com)
• IBM Port Replicator II docking station (PN: 74P6733)

This is what you need to do:

1. Uninstall existing IBM Radeon video drivers
2. Download DHmodtool3.exe and ATI Catalyst 6.5 drivers (non-mobile version). Make sure you have .NET Framework 2.0 installed for the ATI Catalyst control panel.
3. Install the ATI Catalyst drivers and Control Center using DHmodtool.
4. Insert the T30 into the Port Replicator II and firmly attach the Monster Cable DVI400-1M to the monitor.
5. Open the ATI Catalyst control center and enable the DVI monitor at 1920x1200 @60Hz. If you receive video noise, turn on "Reduce DVI Frequency" in the Digital Flat Panel options in the control center.

Copyright 2006 by Jonathan Cox. All rights reserved.

8/7/2006