sudo apt-key add -
sudo apt-get update
然后运行sudo intel-graphics-update-tool会出现如下错误提示：
W:GPG error: https://download.01.org/gfx/ubuntu/16.04/main xenial InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 56A3DEF863961D39, W:The repository 'https://download.01.org/gfx/ubuntu/16.04/main xenial InRelease' is not signed., W:Data from such a repository can't be authenticated and is therefore potentially dangerous to use., W:See apt-secure(8) manpage for repository creation and user configuration details., W:There is no public key available for the following key IDs:
56A3DEF863961D39 , E:Problem executing scripts APT::Update::Post-Invoke-Success 'if /usr/bin/test -w /var/cache/app-info -a -e /usr/bin/appstreamcli; then appstreamcli refresh > /dev/null; fi', E:Sub-process returned an error code
解决方法是添加两个签名：
wget --no-check-certificate https://download.01.org/gfx/RPM-GPG-KEY-ilg -O -
关键词：Ubuntu16.04安装Intel显卡驱动(处理Intel HD Graphics 630问题)