Does VT-d need hardware support (besides the CPU)

motherboardvirtualizationvt-d

I have a Z68 motherboard that is capable to run an Ivy Bridge CPU which features VT-d. Currently, I do not have such a CPU, but I plan to upgrade it so I am able to pass PCI devices (Ethernet and graphics card) to a QEMU machine for testing.

However, I see much contradictory information on the support of VT-d for this Z68 motherboard.

Assume that a CPU supports VT-d. Is motherboard support for VT-d determined by software (BIOS) or hardware (some additional chips or hardware logic)?

Best Answer

I am now running an i7 3770 with a GA-Z68X-UD3H-B3 (rev 1.3) motherboard on BIOS U1l. VT-d seems to work, I can successfully pass PCI devices to a QEMU instance.

Modern Intel CPUs have the North bridge integrated in the CPU package. Thus, at least for the Sandy Bridge and Ivy Bridge CPUs, the VT-d functionality is provided by the CPU itself (the hardware part). The BIOS must still be configured to provide the necessary information toe the host (software). There does not seem to be an additional hardware requirement if I am not mistaken.

(source: pure guess-work and anecdotal evidence from myself)