Bonjour Denis,
Voici le résultat de dxdiag:
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System Information
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Time of this report: 9/2/2010, 11:47:23
       Machine name: xxx
   Operating System: Windows 7 Édition Familiale Premium 64-bit (6.1, Build 7600) (7600.win7_gdr.100618-1621)
           Language: French (Regional Setting: French)
System Manufacturer: System manufacturer
       System Model: System Product Name
               BIOS: BIOS Date: 01/28/10 17:20:14 Ver: 08.00.15
          Processor: Intel(R) Core(TM) i7 CPU         920  @ 2.67GHz (8 CPUs), ~2.7GHz
             Memory: 6144MB RAM
Available OS Memory: 6136MB RAM
          Page File: 1902MB used, 8327MB 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 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.
        Sound Tab 3: 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 GTX 285 
       Manufacturer: NVIDIA
          Chip type: GeForce GTX 285
           DAC type: Integrated RAMDAC
         Device Key: Enum\PCI\VEN_10DE&DEV_05E3&SUBSYS_18801462&REV_A1
     Display Memory: 3817 MB
   Dedicated Memory: 1005 MB
      Shared Memory: 2811 MB
       Current Mode: 1680 x 1050 (32 bit) (60Hz)
       Monitor Name: Moniteur Plug-and-Play générique
      Monitor Model: L222W
         Monitor Id: GSM5664
        Native Mode: 1680 x 1050(p) (59.883Hz)
        Output Type: HD15
        Driver Name: nvd3dumx.dll,nvwgf2umx.dll,nvwgf2umx.dll,nvd3dum,nvwgf2um,nvwgf2um
Driver File Version: 8.17.0011.9745 (English)
     Driver Version: 8.17.11.9745
        DDI Version: 10
       Driver Model: WDDM 1.1
  Driver Attributes: Final Retail
   Driver Date/Size: 4/3/2010 22:55:32, 11906664 bytes
        WHQL Logo'd: n/a
    WHQL Date Stamp: n/a
  Device Identifier: {D7B71E3E-46A3-11CF-C351-8B381FC2C535}
          Vendor ID: 0x10DE
          Device ID: 0x05E3
          SubSys ID: 0x18801462
        Revision ID: 0x00A1