I've been plagued by short total freeze ups on this system since I built it.  Where everything, video, sound, keyboard, mouse will freeze up for 5-10 seconds then return to normal.  About every third or forth time this happens the whole screen will blackout for half a second at the end of the freeze up and come back with the message.  
"Display NVIDIA Windows Kernel Mode Driver, version 197.45 stopped responding and has successfully recovered"
Problem started in Vista and has continued since I got 7.
I just updated to 197.45 last week to see if that would help, and the problem has actually now become more frequent.  It really sucks in the middle of a low dogfight to have everything freeze for 10 seconds, and come back to "you have crashed"
This is not strictly an AH problem it happens in any program, but perhaps more often in AH, or maybe that's just my perception I haven't actually logged them.
DXdiag:
System Information
------------------
Time of this report: 4/15/2010, 22:41:04
       Machine name: KIRK-PC
   Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7600) (7600.win7_gdr.100226-1909)
           Language: English (Regional Setting: English)
System Manufacturer: Gigabyte Technology Co., Ltd.
       System Model: EP45-UD3P
               BIOS: Award Modular BIOS v6.00PG
          Processor: Intel(R) Core(TM)2 Quad CPU    Q8200  @ 2.33GHz (4 CPUs), ~2.3GHz
             Memory: 6144MB RAM
Available OS Memory: 6142MB RAM
          Page File: 1332MB used, 10950MB 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: 6.01.7600.16385 64bit Unicode
------------
DxDiag Notes
------------
      Display Tab 1: No problems found.
        Sound Tab 1: No problems found.
        Sound Tab 2: No problems found.
          Input Tab: No problems found.
--------------------
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)
---------------
Display Devices
---------------
          Card name: NVIDIA GeForce 8400 GS   
       Manufacturer: NVIDIA
          Chip type: GeForce 8400 GS
           DAC type: Integrated RAMDAC
         Device Key: Enum\PCI\VEN_10DE&DEV_06E4&SUBSYS_82BC1043&REV_A1
     Display Memory: 3310 MB
   Dedicated Memory: 495 MB
      Shared Memory: 2815 MB
       Current Mode: 1920 x 1080 (32 bit) (60Hz)
       Monitor Name: Generic PnP Monitor
      Monitor Model: X233H
         Monitor Id: ACR009A
        Native Mode: 1920 x 1080(p) (60.000Hz)
        Output Type: HD15
        Driver Name: nvd3dumx.dll,nvwgf2umx.dll,nvwgf2umx.dll,nvd3dum,nvwgf2um,nvwgf2um
Driver File Version: 8.17.0011.9713 (English)
     Driver Version: 8.17.11.9713
        DDI Version: 10
       Driver Model: WDDM 1.1
  Driver Attributes: Final Retail
   Driver Date/Size: 3/16/2010 00:51:59, 11906152 bytes
        WHQL Logo'd: Yes
    WHQL Date Stamp: 
  Device Identifier: {D7B71E3E-45A4-11CF-0256-B7A21FC2C535}
          Vendor ID: 0x10DE
          Device ID: 0x06E4
          SubSys ID: 0x82BC1043-------------
Sound Devices
-------------
            Description: Speakers (Realtek High Definition Audio)
 Default Sound Playback: Yes
 Default Voice Playback: Yes
            Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0885&SUBSYS_1458A102&REV_1001
        Manufacturer ID: 1
             Product ID: 100
                   Type: WDM
            Driver Name: RTKVHD64.sys
         Driver Version: 6.00.0001.5780 (English)
      Driver Attributes: Final Retail
            WHQL Logo'd: Yes
          Date and Size: 1/20/2009 00:12:54, 1699744 bytes
            Other Files: 
        Driver Provider: Realtek Semiconductor Corp.
         HW Accel Level: Basic
              Cap Flags: 0xF1F
    Min/Max Sample Rate: 100, 200000
Static/Strm HW Mix Bufs: 1, 0
 Static/Strm HW 3D Bufs: 0, 0
              HW Memory: 0
       Voice Management: No
 EAX(tm) 2.0 Listen/Src: No, No
   I3DL2(tm) Listen/Src: No, No
Sensaura(tm) ZoomFX(tm): No
            Description: Realtek Digital Output (Realtek High Definition Audio)
 Default Sound Playback: No
 Default Voice Playback: No
            Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0885&SUBSYS_1458A102&REV_1001
        Manufacturer ID: 1
             Product ID: 100
                   Type: WDM
            Driver Name: RTKVHD64.sys
         Driver Version: 6.00.0001.5780 (English)
      Driver Attributes: Final Retail
            WHQL Logo'd: Yes
          Date and Size: 1/20/2009 00:12:54, 1699744 bytes
            Other Files: 
        Driver Provider: Realtek Semiconductor Corp.
         HW Accel Level: Basic
              Cap Flags: 0xF1F
    Min/Max Sample Rate: 100, 200000
Static/Strm HW Mix Bufs: 1, 0
 Static/Strm HW 3D Bufs: 0, 0
              HW Memory: 0
       Voice Management: No
 EAX(tm) 2.0 Listen/Src: No, No
   I3DL2(tm) Listen/Src: No, No
Sensaura(tm) ZoomFX(tm): No
---------------------
Sound Capture Devices
---------------------
            Description: Microphone (Realtek High Definition Audio)
  Default Sound Capture: Yes
  Default Voice Capture: Yes
            Driver Name: RTKVHD64.sys
         Driver Version: 6.00.0001.5780 (English)
      Driver Attributes: Final Retail
          Date and Size: 1/20/2009 00:12:54, 1699744 bytes
              Cap Flags: 0x1
           Format Flags: 0xFFFFF
            Description: Realtek Digital Input (Realtek High Definition Audio)
  Default Sound Capture: No
  Default Voice Capture: No
            Driver Name: RTKVHD64.sys
         Driver Version: 6.00.0001.5780 (English)
      Driver Attributes: Final Retail
          Date and Size: 1/20/2009 00:12:54, 1699744 bytes
              Cap Flags: 0x1
           Format Flags: 0xFFFFF
-------------------
DirectInput Devices
-------------------
      Device Name: Mouse
         Attached: 1
    Controller ID: n/a
Vendor/Product ID: n/a
        FF Driver: n/a
      Device Name: Keyboard
         Attached: 1
    Controller ID: n/a
Vendor/Product ID: n/a
        FF Driver: n/a
      Device Name: Logitech Extreme 3D
         Attached: 1
    Controller ID: 0x0
Vendor/Product ID: 0x046D, 0xC215
        FF Driver: n/a
Poll w/ Interrupt: No
-----------
USB Devices
-----------
+ USB Root Hub
| Vendor/Product ID: 0x8086, 0x3A35
| Matching Device ID: usb\root_hub
| Service: usbhub
| Driver: usbhub.sys, 7/13/2009 18:07:09, 343040 bytes
| Driver: usbd.sys, 7/13/2009 18:06:23, 7936 bytes
----------------
Gameport Devices
----------------
------------
PS/2 Devices
------------
+ Standard PS/2 Keyboard
| Matching Device ID: *pnp0303
| Service: i8042prt
| Driver: i8042prt.sys, 7/13/2009 17:19:57, 105472 bytes
| Driver: kbdclass.sys, 7/13/2009 19:48:04, 50768 bytes
| 
+ HID Keyboard Device
| Matching Device ID: hid_device_system_keyboard
| Service: kbdhid
| Driver: kbdhid.sys, 7/13/2009 18:00:20, 33280 bytes
| Driver: kbdclass.sys, 7/13/2009 19:48:04, 50768 bytes
| 
+ Terminal Server Keyboard Driver
| Matching Device ID: root\rdp_kbd
| Upper Filters: kbdclass
| Service: TermDD
| Driver: i8042prt.sys, 7/13/2009 17:19:57, 105472 bytes
| Driver: kbdclass.sys, 7/13/2009 19:48:04, 50768 bytes
| 
+ PS/2 Compatible Mouse
| Matching Device ID: *pnp0f13
| Service: i8042prt
| Driver: i8042prt.sys, 7/13/2009 17:19:57, 105472 bytes
| Driver: mouclass.sys, 7/13/2009 19:48:27, 49216 bytes
| 
+ HID-compliant mouse
| Matching Device ID: hid_device_system_mouse
| Service: mouhid
| Driver: mouhid.sys, 7/13/2009 18:00:20, 31232 bytes
| Driver: mouclass.sys, 7/13/2009 19:48:27, 49216 bytes
| 
+ Terminal Server Mouse Driver
| Matching Device ID: root\rdp_mou
| Upper Filters: mouclass
| Service: TermDD
| Driver: termdd.sys, 7/13/2009 19:45:55, 62544 bytes
| Driver: sermouse.sys, 7/13/2009 18:00:20, 26624 bytes
| Driver: mouclass.sys, 7/13/2009 19:48:27, 49216 bytes
------------------------
Disk & DVD/CD-ROM Drives
------------------------
      Drive: C:
 Free Space: 112.6 GB
Total Space: 152.6 GB
File System: NTFS
      Model: WDC WD1600AAJB-00PVA0 ATA Device
      Drive: E:
 Free Space: 419.9 GB
Total Space: 476.9 GB
File System: NTFS
      Model: GRAID  SCSI Disk Device
      Drive: F:
      Model: WHEHSX K52VWXIBSL SCSI CdRom Device
     Driver: c:\windows\system32\drivers\cdrom.sys, 6.01.7600.16385 (English), 7/13/2009 17:19:54, 147456 bytes
      Drive: D:
      Model: HL-DT-ST DVD-RAM GSA-H54N ATA Device
     Driver: c:\windows\system32\drivers\cdrom.sys, 6.01.7600.16385 (English), 7/13/2009 17:19:54, 147456 bytes