I HAVE NO VIDEO SUPPORT. This crap can't run anything, not even stupid 480p video. What the hell is YOUR problem?
You're winey attitude. It's not conducive to people wanting to help you. No one likes a winey s**t who complains all the time, even when they want help.
I've installed the Win8.1 driver that fully supports my graphic card and the Youtube was still lagging like I'm trying to view it on Commodore C128...
It sounds like the driver still isn't loaded up. Does it say it's AMD's driver in device manager because it sounds like you're still on that generic driver. Also yes, the generic driver is going to suck but at least you can see what you're doing to install the right one. That's the point of it...
So lets see Device Manager. The driver should say the driver provider is AMD and not Microsoft. If it says Microsoft, the driver never actually loaded it. It's entirely possible that it might not want to load the older driver through the installer and that you might have better luck manually installing it. Honestly, if you've tried several versions of catalyst without using a driver cleaner, I would clean up the PC again and attempt to install the one that worked with 8.1 again. If it still holds on to the Microsoft driver, you may want to try manually updating it through the device manager by telling it what .inf file should get loaded up for your graphics card if it's an "incompatibility" thing since the old installer might not be Windows 10 aware but, this is all guesswork because we get more ranting than information.
Either way, report back what device manger is. It will illuminate how to proceed and what questions to ask. I'm willing to help so long as you don't turn this thread into a dumping place where rants go to die.
Also, this is all resting on the assumption that you properly removed drivers before installing new ones or that you've successfully attempted to install them. So more info, less ranting please.