Thanks for getting back to our community.
I understand you have some games that required 800*600 screen resolution.
If you are using a monitor that only supports 1280*800, then your games will use same screen resolution, then you may need to adjust resolution within game properties.
It may help if you update your video drivers to the latest version.
Please filter by operating system and try to install the driver when it finishes downloading, to verify that your system will accept it.
Also, check the list of supported games for your graphics controller here: