Hence I want the related ATI Display Drivers.
Then you should contact Sony, because they are still saying not to upgrade Vaio laptops to Windows 10.
Sony eSupport - Windows 10 Upgrade information
Important: Although Microsoft is already offering the Windows 10 upgrade, it is strongly recommended that you wait to install it until the drivers & installation instructions are available for your VAIO PC model.
Sony Vaio..new info Windows 7 SP1
Sony Vaio owners have a few weeks or longer to wait for their Windows 10 upgrade | PCWorld
Also, if switchable Intel/AMD graphics:
Laptops with switchable AMD/Intel graphics Windows 10 support
Keep in mind that Sony no longer manufacturers Vaio and has sold the brand, so IMO compatible drivers are not a priority:
VAIO computers return after Sony sells the brand | The Verge
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