A dxdiag.txt is an textual description of the hardware of your computer as seen from DirectX. These hardware descriptions are very helpfull for giving support and understanding your computer.

To create a dxdiag.txt:

1. Click START.
2. Click Run.
3. Clear the "Open" box and type dxdiag.
4. Click OK.
5. The DirectX Diagnostic Tool will open.
6. Click Save All Information.
7. Save the dxdiag.txt file it to your Desktop.
8. Now you should see a text file called "dxdiag.txt" sitting on your Windows desktop.