Intel Fixes VT-d Bug in Sandy Bridge-E CPUs

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[citation][nom]mouse24[/nom]I am confused, what exactly is VT-d and whats wrong with there being no hardware acceleration? isnt the gpu normally handling that?[/citation]

edit: unless they mean it adds virtualization hardware accel support for virtual cores while running multi threaded apps...
 

dgingeri

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[citation][nom]mouse24[/nom]I am confused, what exactly is VT-d and whats wrong with there being no hardware acceleration? isnt the gpu normally handling that?[/citation]

VT-d is hardware acceleration within the CPU for virtual machines. it has nothing to do with graphics. This is mostly used for (in home and/or regular user situations) virtual machines to run old software that won't run under the current OS, like running Windows XP software in a Windows XP virtual machine while the main OS is Windows 7, or running a Linux virtual machine on a Windows main OS. Most people won't be using it. If they do, VT-d won't make much of a difference for most people.

I do, however. I use it to make multiple virtual machines to learn stuff for IT certifications. Right now, I'm working on my MCITP-VA cert, running multiple virtual machines from my home server (running Windows 2008 R2) so I can get a better job. VT-d missing would mean great trouble for me, if I were to use it as a server. Thankfully, if I were to get one, I wouldn't be using it as a server since I already have that.
 

molo9000

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[citation][nom]SteelCity1981[/nom]For the typical pc user they don't even know what VT-d does let alone use it.[/citation]

The typical PC user doesn't buy a $1000 CPU.
 
[citation][nom]dgingeri[/nom]VT-d is hardware acceleration within the CPU for virtual machines. it has nothing to do with graphics. This is mostly used for (in home and/or regular user situations) virtual machines to run old software that won't run under the current OS, like running Windows XP software in a Windows XP virtual machine while the main OS is Windows 7, or running a Linux virtual machine on a Windows main OS. Most people won't be using it. If they do, VT-d won't make much of a difference for most people.I do, however. I use it to make multiple virtual machines to learn stuff for IT certifications. Right now, I'm working on my MCITP-VA cert, running multiple virtual machines from my home server (running Windows 2008 R2) so I can get a better job. VT-d missing would mean great trouble for me, if I were to use it as a server. Thankfully, if I were to get one, I wouldn't be using it as a server since I already have that.[/citation]

That is not entirely correct.

VT-x is the set of extensions required to properly secure a virtual machine running in long addressing mode and reduce VM reliance on operation emulation. It is the bare minimum required to run an OS safely in 64 bit mode on Intel CPUs (AMD CPUs can run 64 bit guest OSes purely in software but will still see performance benefits from AMD-V).

VT-d and AMD-Vi are the sets of extensions required to properly allow a guest OS access to peripherals without having to go through a software layer. This allows guests to access Ethernet controllers, USB controllers, PCI-E controllers, SATA controllers, etc... VT-d is to the chipset as VT-x is to the CPU.
 

A Bad Day

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[citation][nom]molo9000[/nom]The typical PC user doesn't buy a $1000 CPU.[/citation]
Never underestimate the stupidity and ignorance of humans.

Such as an idiot buying an i7 2600k and pairing it with a motherboard that lacks overclocking support, thinking the integrated graphics is sufficient to run Crysis 2 at Directx 11, high resolutions and details.
 

Trialsking

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[citation][nom]notsleep[/nom]...or a guy spending $4,000 on a laptop for his wife to surf the net with...early adopters are usually not that bright...[/citation]
but it loads the pages SOOOOOO much faster
 

JimmiG

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Wow, that's a pretty serious flaw for the affected users that need it. Surprised we haven't heard much about this before. VT-d or AMD-Vi are absolutely essential for me.
 

CyberAngel

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Looks like even Windows 8 does not use it
or rather I could not quickly find in on the docs currently available for W8
Maybe it comes along later or I was sloppy
Those of you who have a greater tendency to load every doc available (of W8)
may correct this (possible misinfo), please
 


Windows 8 is not a virtualization platform. Most hypervisor based virtualization platforms are focused on resource allocation and consolidation efficiency, and so the server oriented Hyper-V probably wouldn't get any real advantage from VT-d and so I doubt that they would implement it yet.
 
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In other news, the same CPU is still an 8-core with 2 perfectly good cores intentionally disabled, not die harvested like another company would do, as every Intel chip on every wafer is flawless, bug free, and capable of 5ghz on air.

Furthermore, most people who would buy this CPU just want a smoother Facebook experience, not to use as a professional workstation to run those virtual machine thingies, whatever they are. They wouldn't be disappointed at all to pay $1000 for a CPU that has vastly inferior VM performance to a $200 Bulldozer CPU due to lack of proper IO acceleration.
 

lradunovic77

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I received latest ASRock update for C2 and i enabled VT-d on my C1 processor and everything works fine. With proper BIOS update it should be good on C1 CPUs as well.
 

ochentay4

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[citation][nom]gtx_560tiuser[/nom]well at least they fixed it[/citation]
They did not fixed it. Everyone who has a C1 processor is screwed. Thanks god I read this news because I was trying to make a decision between i7-2600 or i7-3960X.

They should offer an exchange them for free (or at least for a shrot fee) because C1 are DEFECTIVE UNITS (like previous TLB fckup on Phenom1).
 

lradunovic77

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With latest BIOS update i enabled it and i have no problems fully using VT-d on my C1. I do lot of virtualization among other things like programming and gaming and i7 i3930K seems running quite happy. Perhaps there are cases where VT-d won't work but i believe with proper Bios update should fix for most people. Again most people don't even use VT-d, it enabled virtualized OS to directly access things like video card so you could basically run Crysis 2 game in there :).
 
Good thing (for Intel that is) that the issue only affected their minor-volume sales product. Imagine if the problem was with Ivy Bridge - it would be the Phenom TLB debacle all over again.
 

emike09

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I just spoke with an Intel rep about this - the issue likes in the BIOS, NOT the CPU iteslf. Each manufacturer should be releases a BIOS update that fixes this issue. C2 CPU's have it fixed in-processor. Nobody is screwed, just contact your MB Manufacturer and get the latest BIOS.
 
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