Recently, I purchased dell cpu with "AMD Radeon R7-450" graphics card. I installed ubuntu16.04 and windows10 OS in my system for my work. I found amd graphics card driver from the dell site for windows10 but I didn't find any driver for ubuntu16.04. Due to this, the text on my screen is large and unable focus on the screen for reading any pdf files or doing any work in ubuntu. I called dell technical support for help on the issue. They replied that dell don't support any software issues related ubuntu (third party company for dell). Finally they suggested to contact AMD or ubuntu. I wrote a mail to AMD technical support and I got this reply
"I understand you are looking for a driver which support Ubuntu 16.04 on your computer with AMD Radeon R7-450 graphics card. I see that this GPU is an OEM manufacture card and there is no drivers support on our websites for this graphics card.
I would like to inform you that AMD releases generic drivers and OEMs like Apple, HP, Dell etc will use this generic drivers and customize them as per OEM requirements and features.
Hence, it is recommended to contact the OEM itself for any drivers and feature support."
Then again I contacted dell and told what AMD support suggested but dell did not give any possible solution for this issue and asked me to contact ubuntu support. So finally I am posting this in this site seeking for any possible solution to fix the problem.