Do not use this article unless you are using CentOS 7.2 - 7.4. If you need instructions for disabling Nouveau for latest CentOS kernels/versions (7.5 - 7.6 at the time of this edit Feb 2019), please use the following article below:
CentOS 7.x NVIDIA Driver installation
When you are installing NVIDIA drivers, and it complains you have Nouveau running. Some GUI related issues with CentOS 7 included in this article.
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