29 replies to this topic

[ikon]

AFAIK, it's not related to performance. It has more to do with certain features that are available with VT-d but not without it. The feature are not needed for basic virtualization but can be useful for more sophisticated setups.

[Joe_Miner]

How much of a hit is lack of Vt-d support for virtualization? I was skimming through this thread when I saw that my 2600K does not support Vt-d. Is this a performance thing? Config thing? Sorry for the noob question.

It's more about keeping future options open -- for the vast majority of us it doesn't make a difference. Tinkertry writes extensively about the advantages of Vt-d so a good place to start IMHO is http://tinkertry.com...virtualization/

[SikSlayer]

What about the UD3H? That's the board I was planning to buy for my next system.

Edited by SikSlayer, 09 May 2012 - 04:51 PM.

[pcdoc]

What about the UD3H? That's the board I was planning to buy for my next system.

The UD3 is great choice as long as you can get by with one less I was looking at that model as well. All you really give up is x16 slot and 3 6G sata ports. If you think you need more than that, better off spending the $50 now.

[SikSlayer]

I'm most interested in VT-d support. If the UD3H has it, that's what I'll be getting.

Edited by SikSlayer, 10 May 2012 - 11:03 AM.

[Joe_Miner]

What about the UD3H? That's the board I was planning to buy for my next system.

It's probably a good idea to go to Gigabyte's web site and download the PDF of the manual for the UD3H and then you could check out the specs on it's support for VT-d. I had been thinking of the GA-Z77X-UD5H so as part of my due dilligence I downloaded their Manual and that's when I found the VT-d support for the board.

Good luck -- let us know what you learn!

[pcdoc]

I'm most interested in VT-d support. If the UD3H has it, that's what I'll be getting.

There is no present or apparent support for VT-d on that board. If you are going to run Hyper-V it does not matter but if you are going play with ESXi, it will give you extra capabilities.

[Jason]

It's more about keeping future options open -- for the vast majority of us it doesn't make a difference. Tinkertry writes extensively about the advantages of Vt-d so a good place to start IMHO is http://tinkertry.com...virtualization/

So my new core i5-3570K CPU supports vt-x (not vt-d). Not to mention the 3570K doesn't support hyper-threading while the core i7-3770K does. If Windows Server 2012 was going to support virtualized gaming in a guest OS as a result of vt-d, I'd buy an i7-3770K right now and not think twice. What are the chances of this? The dilemma: either I return my i5-3570K now and exchange for an i7-3770K or there's no real benefit in a home WS 2008 R2 environment of hyper-threading and vt-d?

I've read the vt-d debate in a few places, but no one that ever provided detail behind what vt-d offers in practical terms.

[timekills]

Well....if you're looking for VT-d then don't swap a "K" processor for another "K" processor. Neither would support VT-d. Although, I know the C2 stepping Sandy Bridge (SB) cpus fixed some Vt-d issues Intel had, and that included their highest end K so I could be wrong.

I use a 2500K (SB) in my 2008R2 board but previously used an i3 530. The i3 530 did support VT-d, while the 2500K does not. I've seen no change in ability, including I can use the SB processor to allow for RemoteFX with the HD3000 integrated graphics. I have had two of my sons use VMs to play Minecraft from their underpowered laptops; if I included a dedicated GPU it would be even better.

Bottom line: I don't know what 2012 will bring, but believe it or not, current MS best practices suggest disabling Vt-d for 2008R2 systems (at least through SP1.) If you're not going ESXi, I wouldn't worry about Vt-d support.

Edit: P.S. Vt-d gives an "improved" IO passthrough by intercepting IRQ requests and passing them directly to the hardware while still keeping the security required in a hypervisor OS. Vt-x does this with memory management; the Vt-d allows for more precise hardware control. MS uses RemoteFX to do the same thing only through software (rather like using OS RAID rather than hardware RAID. The hardware way may be more effective when it works, but you're limited in the hardware specs and need to find drivers...the software version could be slower but it is more readily available. RemoteFX does have some specific hardware requirements though. It is not a panacea.

[ikon]

This whole area of tech reeks of vendor neglect because of consumer indifference.