My Dell Precision M4600 was working fine yesterday. After some applications updated this morning (corporate push), I can no longer use Aero themes and the tool ribbons in Office 365 are filled with black squares. The tech support folks here have given up after trying:
* Uninstall/reinstall recommended driver from Dell: did not change behavior.
* Full Diagnostics run at bootup: no problems found.
* Switching away to another theme and then back: no change.
* No transparency for windows borders
* All Office 2013 products (Outlook, Word, Excel, Lync, etc.) have black squares with a few color pixels on icons, buttons on dialogs are black until I mouse over them, splash screens are empty white rectangles.
* I downloaded and ran MicrosoftFixit.Aero.RNP.Run.exe from Microsoft: "The current video card cannot display Aero effects."...although it did before.
Dell M4600, i7-2720QM CPU
16 GB memory, tons of empty hard drive
Windows 7 with latest patches, 64-bit
BIOS Dell A08, 10/18/2011
AMT (ATI) FirePro M5950 (FireGL) Mobility Pro Graphics
Driver is 8.850.7.5000, which is what Dell's site recommends for my service tag