Hello and welcome to the forums.
Your windows 7 installation is defaulting to Standard VGA Graphics Adapter because it either is not recognizing the adapter you are using or does not have the correct native drivers for the device.
Your best bet is to get on Acer's website and plug in some details regarding your system and see what they have in the way of a driver the provides windows 7 support.
Failing that, you will need to determine the Manufacturer, Model Name, Model Number of the adapter and see if you can obtain a Windows 7 driver from the device manufacturer's website.
If it is a very old legacy device you may have to consider replacing it with a more current mainstream product as some of those older Via / S3 chipsets that Acer integrated onto the motherboards of older systems will be difficult to find suitable drivers for.
Regards
Randy