In most cases, it is either a clash between two graphics cards or an issue with the Intel HD Graphics drivers that causes the gfxui.exe process to use a lot of hard disk bandwidth and lead to high CPU usage. Thankfully, though, this issue can be fixed by simply uninstalling and then reinstalling the Intel HD Graphics drivers. In order to uninstall your computer’s Intel HD Graphics drivers, you need to:
Once your computer boots up, the Intel HD Graphics drivers will have been successfully uninstalled, which means that you are now going to have to reinstall them. In order to do so, go to the official Intel Support website, type the model of your Intel HD Graphics adapter (Intel HD Graphics 4000, for example) into the Search downloads field and press Enter, sift through the search results for the most recently released version of the drivers for your Intel HD Graphics adapter that is compatible with the OS your computer is running on, download the installer for the drivers, run the installer and go through it to reinstall the drivers for the Intel GPU. Once the drivers have been reinstalled, restart your computer and, when it boots up, you should see that you are no longer affected by this problem even though the drivers for both your Intel GPU and your dedicated GPU are installed and both GPUs are working.
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