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Visual corruption - ThinkPad R400, R500, T400, T400s, T500, W500, X200, X200s, X200 Tablet, X301

Lenovo has received reports of two types of visual corruption on the screen.

An example of Type A visual corruption is shown in the image below. It looks like vertical columns of horizontal lines. The corruption will flicker or mostly disappear if you move the mouse.


Example of Type A corruption.

Examples of Type B visual corruption are shown in the images below. It tends to start out isolated to one application window along the window borders, but then may start appearing on all of the other application windows, and the desktop. The corruption will typically appear as garbled text or scrambled images.


Example 1 of Type B corruption.


Example 2 of Type B corruption.


Example 3 of Type B corruption.

Affected configurations

In order to experience Type A visual corruption, the following configuration details are also required:

  • Microsoft Windows Vista or Windows 7 (either 32-bit or 64-bit)
  • Intel Graphics Driver version
    • This was the only driver version which Lenovo released that exhibited this problem. There may be additional, non-Lenovo, drivers which show this problem.
    • The Lenovo-released graphics driver packages containing this driver are 7XD551WW (32-bit Windows) and 7XD651WW (64-bit).

In order to experience Type B visual corruption, the following configuration details are required:

  • Microsoft Windows Vista or Windows 7 (either 32-bit or 64-bit)
  • Intel Virtualization Technology for Directed-IO (VT-d) is enabled in the BIOS setup utility.
  • There are two memory DIMMs in the system, and they have a different size (e.g., 2GB and 1GB).

For both types of visual corruption, the problem is seen on any of the following systems with integrated or switchable graphics:

  • ThinkPad R400(*1), R500
  • ThinkPad T400(*1), T400s, T500(*1)
  • ThinkPad W500(*1)
  • ThinkPad X200, X200s, X200 Tablet, X301

*1: For models with switchable graphics, the system must be in integrated graphics mode to see the failure.


Solution - Type A visual corruption

Type A visual corruption is resolved with a new graphics driver.The version which fixes this issue is, and is available at the following URLs:

32-bit operating system, 7XD552WW
64-bit operating system, 7XD552WW


Workaround – Type B visual corruption

Type B visual corruption is a permanent limitation of the Intel chipset. There exists the following three options to work around this issue.

Option 1: Disable Virtualization Technology for Directed-IO (VT-d). This can be done in the BIOS setup utility. When the system is first booting (during POST), press F1 to enter the setup utility. Then enter the Config menu, and the CPU submenu. Change VT-d to disabled.

Option 2: Make sure that there is only one memory DIMM in the system.

Option 3: Make sure that the two memory DIMMs in the system are of equal size. For example, both are 2GB.


Additional Information

Virtualization Technology for Directed-IO (VT-d) is a hardware assist for virtualizing device IO (primary DMA and interrupts). VT-d is not required to support running a virtual machine (to Lenovo's knowledge at this time). Some VMMs do require that hardware assist for virtualization be enabled, but this is a separate setting from VT-d. In the same BIOS setup screen, there is a setting called Virtualization Technology, which is the more commonly used feature.

Click here for more information on Vt-d.

If you are unable to find what you are looking for, please do try the following options:
1. Lenovo Assisted Search
2. Product usage and general troubleshooting tips
3. Lenovo Support Forum
4. Technical Support Call Centre

Country Availability
Document ID : HT001223
Legacy Document ID : MIGR-74739
Last Updated :
Copyright © Lenovo 2013, all rights reserved
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