This bug has been fairly consistent for me since the game came out 2 weeks ago. Periodically (at least 5 times per playing hour), the game will essentially ALT TAB to display my desktop mid-action. It only briefly shows my desktop (2-5 seconds) and then it resumes normal play. I cannot interact with my desktop when this happens as it is just a brief flash. This is kind of an annoying bug because I have died several times as a result of the game continuing but I cannot interact in anyway while the ALT Tab process occurs.

My gut tells me it is something in the video processing but I am not sure. This issue has happened on all 5 classes of characters I have. It has happened on many different quests and/or Acts (I am in Act III on normal).

I have the full export of dxdiag if you need it but here some basic information including video driver info. My GTS 250 drivers and DirectX 11 is up to date.

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System Information
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Time of this report: 5/29/2012, 19:42:15
Machine name: --------------
Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.120330-1504)
Language: English (Regional Setting: English)
System Manufacturer: Dell Inc.
System Model: Studio XPS 7100
BIOS: Default System BIOS
Processor: AMD Phenom(tm) II X6 1045T Processor (6 CPUs), ~2.7GHz
Memory: 8192MB RAM
Available OS Memory: 8192MB RAM
Page File: 3522MB used, 12858MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7601.17514 32bit Unicode

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DxDiag Notes
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Display Tab 1: No problems found.
Sound Tab 1: No problems found.
Sound Tab 2: No problems found.
Input Tab: No problems found.

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DirectX Debug Levels
--------------------
Direct3D: 0/4 (retail)
DirectDraw: 0/4 (retail)
DirectInput: 0/5 (retail)
DirectMusic: 0/5 (retail)
DirectPlay: 0/9 (retail)
DirectSound: 0/5 (retail)
DirectShow: 0/6 (retail)

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Display Devices
---------------
Card name: NVIDIA GeForce GTS 250
Manufacturer: NVIDIA
Chip type: GeForce GTS 250
DAC type: Integrated RAMDAC
Display Memory: 4069 MB
Dedicated Memory: 997 MB
Shared Memory: 3071 MB
Current Mode: 1920 x 1080 (32 bit) (59Hz)
Monitor Name: Dell ST2410(Digital)
Monitor Model: DELL ST2410
Monitor Id: DELA05C
Native Mode: 1920 x 1080(p) (60.000Hz)
Output Type: DVI
Driver Name: nvd3dumx.dll,nvwgf2umx.dll,nvwgf2umx.dll,nvd3dum,nvwgf2um,nvwgf2um
Driver File Version: 8.17.0012.9573 (English)
Driver Version: 8.17.12.9573
DDI Version: 10
Driver Model: WDDM 1.1
Driver Attributes: Final Retail
Driver Date/Size: 2/9/2012 22:43:00, 17642816 bytes
WHQL Logo'd: Yes
WHQL Date Stamp:
Device Identifier: {D7B71E3E-4555-11CF-BB5F-9F251CC2C535}
Vendor ID: 0x10DE
Device ID: 0x0615
SubSys ID: 0x0593196E
Revision ID: 0x00A2