Windows 7: Problem Nvidia Geforce 8400M GT GPU

Hello
Recently i updated my laptop Sony Vaio VGN-FZ21M from windows vista home 32 to windows 7 ultimate 64. I didn't update teh OS, i just formatted and reisntalled it from bios. Now i can't find the right drivers for my Graphic Nvidia Geforce 8400M GT GPU. Drivers from geforce website are not working, i get an error message showing that the hardware is not detected.. so i tried to download from Sony support center, but they don't have the drivers for 7 64, just vista 32.
What should i do? any suggestion? I was thinking to reinstall vista 32 and then update it to 7.. If i can't find them
Thanks in advice to all!

these are the latest 74 bit ones from Nvidia so they should work NVIDIA DRIVERS 285.62 WHQL

They don't work, the installation fails because it doesn't recognize the hardware. I found online that i can only download drivers from the sony website, but they give just 32bit version.

seems there is already a post here Windows not recognizing NVidia GeForce 8400M GT
hope it helps

Nothing, it doesnt work
Any other ideas?

Try drivers from this website
Drivers | drivers for mobile cards and laptops | laptopvideo2go.com

Still the same problem... They don't work

I resolved installing a 32bit version of windows 7. Computer recognizes the card with sony drivers this way. I wonder if 8400M GT doesnt work with 64bit or it's just me

VGN-FZ21M | VAIO and Computing | VAIO | Updates : Sony, Technical support

It was origianlly set up to run XP 32bit. So the CPU etc. most likely will not run any 64bit software.
I'm actually surprised the Win 7 64bit installed.
See above link.

So Windows 7 32bit is all you can use it would appear.

The latest graphics driver is available here direct from Nvidia.> http://www.nvidia.com/Download/index.aspx?lang=en-us