Hi Alejandro,
Have you tried to make Windows to find a proper
driver online?
I'm using the Geforce
Go 7300 on my laptop and after the installation I had the same problem you have. I just went to the device manager (right click on "computer", then properties and "devise manager" on the left column, open the "display adapters", right click on "Standard VGA Graphics Adapter" and "update
driver software", then "search automatically for updated
driver software" and it should search, find and install the driver (if available)
It worked for me, I hope it works for you.