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Fair warning, I am new to Ubuntu (coming from windows), so you may have to dumb some things down. I got a desktop for christmas. It is a pre-built used desktop. It has absolutely no drivers on it currently. I actually somehow managed to get minecraft working, but then I realized the graphics were horrible! I also have no sound. I googled and googled so that I could figure what the heck graphics card I have and came up with this info
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Barts XT [Radeon HD 6870]
Now, I have googled and googled to figure how to get the drivers for it, to no avail. I did find somewhere that told me to look in the additional drivers but the only thing is there is Unknown: Unknown. I am scratching my head and going nuts trying to figure this all out. If you need additional info, you will probably need to tell me how to find it.