Intel VT-d, will I ever need it? (versus Intel HD Graphics 4000)

[Thinkcat]

Hello

I'm planning my first Hackintosh. Willing to settle upon a CPU, I quickly checked through Wikipedia:

http://en.wikipedia.org/wiki/List_o...ors#.22Ivy_Bridge.22_.28quad-core.2C_22_nm.29
List of Intel Core i5 microprocessors

There is i5 3570K. I want a 4-core machine, but will not spend enough to get an i7. Besides, I dislike HyperThreading. I use my current Macintosh to run Windows and linux in virtual machines. I use Parallels Desktop, but also own a license to the latest VMWare Fusion.

I saw that 3570K is missing VT-d, that is IOMMU virtualization. Looking at what processors Apple is using in its machines, it seems to me that those all have VT-d, including the i5 in my current Mac Mini. I have no idea if Mac Mini's motherboard or chipset take advantage of it, or even if they would, do Parallels Desktop or VMWare Fusion support it.

I know (or at least I assume) that for everyday use, it really does not matter. But those who have built a hackintosh before and used it for serious desktop virtualization, what are your thoughts on this?

It would be no loss to get a i5-3570 without the K. Except that 3570K has HD Graphics 4000 included. Assuming I will buy a separate video card, in what cases or how soon would I be happy to have the HD 4000 onboard anyway?

Or, to put it another way. Do you know (or can you imagine) a case where I would be happy to have VT-d and not miss HD Graphics 4000?

 

[Thinkcat]

Well. Everybody is free to further add details here. But. It seems like VT-d has only recently been supported in Parallels Desktop. So, everything that people have done virtualizing things on their Macs, up to now, has happened without VT-d.

Additionally, VT-d requires support from the chipset. Many Macs, with processors supporting VT-d, have not had a chipset that would enable it.

VT-d is used for level 1 hypervisors and directly connecting hardware, past the host OS, to a virtual machine. I am not sure and I doubt it very much that the way Parallels Desktop uses USB devices has anything to do with this.

I also will not be doing any nested virtualization or developing mobile applications. There was some use case there that got some benefit from VT-d but I can't remember what it was.

 

[zaptoons]

Frankly, I have no idea what VT-d even is or does. Seems like unlocked Intel CPUS don't have it.

Virtual machines run just fine with the VT enabled with the 2600K, 3570K and 3770K machines that I've built, using Parallels and VMFusion. No idea what if any benefit VT-d would add as for actual virtual machine performance.

 

[Bimmer325Ci]

There are NO PROGRAMS that work on OS X that support VT-d, NONE!! I did the research, contacted the big three, Parallels Desktop 8, VMWare Fusion 5 and Virtualbox. They all replied that they do not support VT-d in OS X, maybe with future releases. Trust me, I wish it would work. But for now, we don't have support for VT-d. In other words, there is no reason to enabled it in BIOS/UEFI.

 

[fussie]

Hmm, I've tried both Parallels and VirtualBox but none of them worked for me. (VT-d disabled in BIOS). Came up with a message to say that VT-d is locked.

Zaptoons, were you able to run virtual machines on an i5-3570k with VT-d set to disabled?

Would appreciate any help in getting virtual machines to work as so far I haven't had any luck. Assumed it was due to VT-d being disabled in BIOS, and turning it on would cause my hackintosh to fail to boot (10.8.3).

 

[Bimmer325Ci]

Hmm, I've tried both Parallels and VirtualBox but none of them worked for me. (VT-d disabled in BIOS). Came up with a message to say that VT-d is locked.

Zaptoons, were you able to run virtual machines on an i5-3570k with VT-d set to disabled?

Would appreciate any help in getting virtual machines to work as so far I haven't had any luck. Assumed it was due to VT-d being disabled in BIOS, and turning it on would cause my hackintosh to fail to boot (10.8.3).

"K" versions of Intel CPU's do not support VT-d. All you need to run VM's is VT-x (Intel Virtualization), that needs enabled in BIOS. I think some people get them confused. VT-d is just an extension of VT-x, it adds more options, per say. You don't need it, plus there is no software support for it under OS X right now.

 

[fussie]

Genius! Thank you very much Bimmer325CI. That explained it perfectly. Restarted, enabled, still booted without a problem and loaded VMs fine!