I just started recieving this error as well while playing Call of Duty Modern Warfare 2 (Multiplayer). I know it's very long but here is my DxDiag.txt file. If you're just wondering the version it's DirectX 11 and I was running the game at the min. for video settings (i.e. lowest resolution). I deleted almost everything I didn't think was needed as it's quite long (and didn't seem likely related). I'll also note that I'm using RivaTuner as well. I am not over/underclocking though... just using them to keep my cards cooler. The 2 cards run between 45 to 60 degrees C.
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System Information
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Time of this report: 1/25/2010, 16:23:12
Machine name: DELL-HEATER
Operating System: Windows Vista™ Home Premium (6.0, Build 6002) Service Pack 2 (6002.vistasp2_gdr.090803-2339)
Language: English (Regional Setting: English)
System Manufacturer: Dell Inc.
System Model: Dell XPS720
BIOS: Phoenix ROM BIOS PLUS Version 1.10 A06
Processor: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz (4 CPUs), ~2.4GHz
Memory: 2044MB RAM
Page File: 1803MB used, 3241MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
DxDiag Version: 7.00.6002.18107 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
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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
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Card name: NVIDIA GeForce 8600 GTS
Manufacturer: NVIDIA
Chip type: GeForce 8600 GTS
DAC type: Integrated RAMDAC
Device Key: Enum\PCI\VEN_10DE&DEV_0400&SUBSYS_043810DE&REV_A1
Display Memory: 1009 MB
Dedicated Memory: 243 MB
Shared Memory: 765 MB
Current Mode: 1920 x 1200 (32 bit) (60Hz)
Monitor: Dell 2407WFP-HC (Digital)
Driver Name: nvd3dum.dll,nvwgf2um.dll,nvwgf2um.dll
Driver Version: 8.17.0011.9621 (English)
DDI Version: 10
BGRA Supported: Yes
Driver Attributes: Final Retail
Driver Date/Size: 1/11/2010 21:03:33, 9388648 bytes
WHQL Logo'd: Yes
WHQL Date Stamp:
Device Identifier: {D7B71E3E-4740-11CF-FB56-33241FC2C535}
Vendor ID: 0x10DE
Device ID: 0x0400
SubSys ID: 0x043810DE
Revision ID: 0x00A1
Revision ID: 0x00A1
Video Accel: ModeMPEG2_A ModeMPEG2_C ModeVC1_C ModeWMV9_C
DDraw Status: Enabled
D3D Status: Enabled
AGP Status: Enabled
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System Devices
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Name: AGEIA PhysX 100 Series PCI Card
Device ID: PCI\VEN_1971&DEV_1011&SUBSYS_00011043&REV_00\4&25DB9FF8&0&2878
Driver: C:\Windows\system32\DRIVERS\physX32.sys, 1.01.0001.0015 (English), 2/29/2008 10:18:38, 120960 bytes