I have the same problem with this video card before, what u need to do is download the driver on nvidia, i think the version is 195.62, and make these changes, if ur windows are 64-bits:
1- Exctract the driber instalation in one folder, but dont execute. Go to the folder extracted, in my case was H:\Driver\NVIDIA\DisplayDriver\195.62\WinVista_Win7_64.
2- Find the ID of the video card. Enter in device manager, go on video adapters, select properties of ur video card, go in details. Where is device description change in ID Hardware. U will see a code in this format:
PCI\VEN_10DE&DEV_0426&SUBSYS_9005104D&REV_A1 keep the part in red of the code saved on a text document.
3- Open ListDevices.txt search for ur video card, u will see that this driver is for ur video card, but u have to do some changes. Below the name of the video card add ur video card.My ListDevices is like this:
NVMT.INF:
DEV_0405&SUBSYS_82271071 "NVIDIA GeForce 9500M GS"
DEV_0405&SUBSYS_82301071 "NVIDIA GeForce 9500M GS"
DEV_0407&SUBSYS_02841A92 "NVIDIA GeForce 8600M GT"
DEV_0425&SUBSYS_82271071 "NVIDIA GeForce 8600M GS"
DEV_0425&SUBSYS_82531071 "NVIDIA GeForce 8600M GS"
DEV_0426&SUBSYS_55841991 "NVIDIA GeForce 8400M GT"
DEV_0426&SUBSYS_9005104D "NVIDIA GeForce 8400M GT"
The red is my video card code.
4- Now see the NVMT.INF in green, u will open the document text with this name and change some things.
5- In this document search for [NVIDIA_SetA_Devices.NTamd64.6.1] and for [NVIDIA_SetA_Devices.NTamd64.6.1] there u will add below the DEV.0426 ur video card ID, the Section 11 and section 12 in my video card, i dont now how u find, i search on internet and the guy just put section 11 in one part e section 12 on another.
[NVIDIA_SetA_Devices.NTamd64.6.0]
%NVIDIA_DEV.0405.01% = Section001, PCI\VEN_10DE&DEV_0405&SUBSYS_82271071
%NVIDIA_DEV.0405.02% = Section001, PCI\VEN_10DE&DEV_0405&SUBSYS_82301071
%NVIDIA_DEV.0407.01% = Section001, PCI\VEN_10DE&DEV_0407&SUBSYS_02841A92
%NVIDIA_DEV.0425.01% = Section003, PCI\VEN_10DE&DEV_0425&SUBSYS_82271071
%NVIDIA_DEV.0425.02% = Section003, PCI\VEN_10DE&DEV_0425&SUBSYS_82531071
%NVIDIA_DEV.0426.01% = Section005, PCI\VEN_10DE&DEV_0426&SUBSYS_55841991
%NVIDIA_DEV.0426.02% = Section007, PCI\VEN_10DE&DEV_0426&SUBSYS_88971033
%NVIDIA_DEV.0426.03% = Section011, PCI\VEN_10DE&DEV_0426&SUBSYS_9005104D
[NVIDIA_SetA_Devices.NTamd64.6.1]
%NVIDIA_DEV.0405.01% = Section002, PCI\VEN_10DE&DEV_0405&SUBSYS_82271071
%NVIDIA_DEV.0405.02% = Section002, PCI\VEN_10DE&DEV_0405&SUBSYS_82301071
%NVIDIA_DEV.0407.01% = Section002, PCI\VEN_10DE&DEV_0407&SUBSYS_02841A92
%NVIDIA_DEV.0425.01% = Section004, PCI\VEN_10DE&DEV_0425&SUBSYS_82271071
%NVIDIA_DEV.0425.02% = Section004, PCI\VEN_10DE&DEV_0425&SUBSYS_82531071
%NVIDIA_DEV.0426.01% = Section006, PCI\VEN_10DE&DEV_0426&SUBSYS_55841991
%NVIDIA_DEV.0426.02% = Section008, PCI\VEN_10DE&DEV_0426&SUBSYS_88971033
%NVIDIA_DEV.0426.03% = Section012, PCI\VEN_10DE&DEV_0426&SUBSYS_9005104D
6- To finish in the same archive search for Strings , in the end of the document, is where u chose the name who will apear when the driver is installed, my is like this:
[Strings]
DiskID1 = "NVIDIA Windows Vista / Windows 7 (64 bit) Driver Library Installation Disk 1"
NVIDIA = "NVIDIA"
NVIDIA_A = "NVIDIA"
NVIDIA_DEV.0405.01 = "NVIDIA GeForce 9500M GS"
NVIDIA_DEV.0405.02 = "NVIDIA GeForce 9500M GS "
NVIDIA_DEV.0407.01 = "NVIDIA GeForce 8600M GT"
NVIDIA_DEV.0425.01 = "NVIDIA GeForce 8600M GS"
NVIDIA_DEV.0425.02 = "NVIDIA GeForce 8600M GS "
NVIDIA_DEV.0426.01 = "NVIDIA GeForce 8400M GT"
NVIDIA_DEV.0426.02 = "NVIDIA GeForce 8400M GT "
NVIDIA_DEV.0426.03 = "NVIDIA GeForce 8400M GT (Sony VAIO)"
NVIDIA_DEV.0427.01 = "NVIDIA GeForce 8400M GS"
All the changes i made are in red, i hope this help u. Sorry for the english i ma from brasil and i I do not write well yet:)
If anyone knows please explain why the section 12 and section 11.