Windows Blue Screen When Communicating With PCIe Card

Tech Note: TN2102
Product: TDT Drivers, PO5e, PO5c, PO8e
Version: All
Date Added: 2021-10-11

Issue

Newer PCs that have a recent update of Windows might Blue Screen when TDT applications access the hardware (e.g. when starting a recording in Synapse or running a Transfer Test in zBusMon).

In Windows 10 version 1803, Microsoft introduced a new feature called Kernel DMA Protection to protect PCs against attacks using externally accessible PCIe ports (for example, Thunderbolt™ 3 ports). In Windows 10 version 1903, Microsoft expanded the Kernel DMA Protection support to cover internal PCIe ports. Kernel DMA Protection interferes with the TDT PCIe card and must be disabled.

For more background information, click here.

Workaround

To verify Kernel DMA Protection is on:

  1. From your Windows PC press the Windows key on the keyboard and then the 'R' key, then release the Windows key.

  2. Type 'msinfo32' in the field and press Enter.

  3. Verify that 'Kernel DMA Protection' is 'On'.

You may need help from your IT department / PC vendor on how to turn 'Kernel DMA Protection' off. Typically, there is a BIOS setting called 'VT for Direct IO' (VT-d) or similar that must be disabled. The exact instructions for this differ by manufacturer. If you are unable to find this setting contact the PC manufacturer. For Alienware computers look for the "VT for Direct I/O" BIOS setting in Advanced > Advanced BIOS Features. Here are the steps for most other Dell computers:

  1. Press and hold the Shift key on your keyboard > restart your PC > release the Shift key.

  2. Navigate to the 'Troubleshoot' section and then 'Advanced Options'

  3. Select 'UEFI Firmware Settings' and then click the 'Restart' button

  4. Select 'Boot Config' and scroll down to 'Virtualization Support'

  5. Find 'VT for Direct IO' (VT-d). Turn this off.

  6. Select 'Apply Changes' and then click 'Exit'

To verify Kernel DMA Protection is off:

  1. Press the Windows key on the keyboard and then the 'R' key, then release the Windows key.

  2. Type 'msinfo32' in the field and press Enter.

  3. Verify 'Kernel DMA Protection' is now 'Off'.

Retest your TDT hardware by running a Transfer Test in zBusMon.

Contact TDT support support@tdt.com if you need additional assistance.