Following many tutorials, they ask you to alter the grup file at the /boot/grup/grup.conf.. but in Centos7 there is no /boot/grup/grup.conf
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Activate Intel VT-d in the kernel Activate Intel VT-d in the kernel by appending the intel_iommu=on parameter to the kernel line of the kernel line in the /boot/grub/grub.conf file. The example below is a modified grub.conf file with Intel VT-d activated.
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Fedora Server (2.6.18-190.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-190.el5 ro root=/dev/VolGroup00/LogVol00 rhgb quiet intel_iommu=on
initrd /initrd-2.6.18-190.el5.img
?? how to activate the inter vt-d