Shopping for CPUs based upon Extensions?

One of the biggest disappointments I had with my 2500K that I purchased 4 years ago was when I found out that the cpu didn't support VT-x. This occurred when I had hopes of running Windows in a VM with a Linux host and passing a GPU to it for gaming purposes. While the 2500K is still relevant for gaming, I see the upgrade point finally arriving soon as new technologies are finally worth upgrading to (ex: NVMe). A bit more research into the more technical differences between intel and AMD has me curious about the difference in CPU extensions.

My question is, how much importance should someone place into specifically processor extensions (FMA, BMI, TBM, etc) when deciding what processor to purchase? What extensions are valuable in the current market?

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I suppose you mean VT-d :)

How much importance should you place into processor extensions when CPU shopping?
As much as your use case requires. Or what features your programs require / can benefit from.

You need VT-d? Well buy a CPU that has VT-d support and make sure the motherboard/chipset supports it as well.
Your application supports AVX2 and you'd like that speed boost? Well buy a CPU that has AVX2.
Your application supports FMA3 and you'd like that speed boost? Well buy a CPU that has FMA3.
Your application supports TSX-NI and you'd like that speed boost? Well buy a CPU that has TSX-NI.

I could go on forever?

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as @Lagittaja said, if the extensions you are shopping for are important to you then you should place more value on them.

@Lagittaja I suppose the further point of discussion here is then is what are the benefit for Intel to segment their products into different markets as opposed to what appears, from the AMD side, to be just include everything into all of their products? If say someone wants a cpu for x purpose, why buy a specialized product that may be faster single threaded performance compared to a product with extensions that could help with x purpose run faster?

Profit. Also why? Because they can.
Where's the competition?

But at least they've rolled VT-d back to the K SKU's (since 4790K) and all of the consumer Skylake chipsets support it. If the motherboard manufacturer doesn't enable it, well.. Tough.

Because Intel and OEM's et. al. and whatnot.
This is a good read if you haven't stumbled on it already

But this whole conversation is pointless.
The consumer or client buys the CPU (or system) that suits his/her needs and is within his/her budget.
If Intel CPU X meets his/her needs and budget then that's that.
If AMD CPU Y meets his/her needs and budget then that's that.
End of story.
If the consumer or client is stupid and doesn't understand the features or his/her needs, well.. Tough.

Edit: Also "may be faster in single threaded performance"? Since when has AMD catched up with Intel? Zen isn't out yet as far as I'm aware.
That's the closest thing we have in clock-for-clock comparisons. [email protected] vs [email protected]

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That's my question, in what world does shopping for processors based upon extensions out weigh the benefits of a processor that is just flat out faster because it has dedicated FPUs for better single threaded performance (see intel for the past several years). Case in point, I was not aware when I purchased my 2500k that I would want to use my computer to the point that I am running Linux with a Windows guest, passing through a secondary GPU to it. Fast forward 4 years and I've reached buyers remorse. Sure you can say I've outgrown my current hardware's features; but does this give credence to buying hardware with a full set of features as opposed to hardware which has great performance and overclocks fantastically like Sandy Bridge did?

I got a great reply on reddit of all places, explaining it:

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I would say your best bet would be an i5 or i7 devils canyon or Skylake.
Of course the HT on the i7 would be a benefit for virtualization.
4790K or 6700K would realy be a good choice.
Especialy because they have an igpu, which means that you basicly only need 1 dedicated gpu for passtrough.

AMD FX cpu´s are basicly also good at virtualization.
But the only down side of these chips is the poor per core performance.
And the lack of an igpu, which means that you would be needing 2 gpu´s.
And preferably a 990FX chipset board if you like to run them both at 16x speeds.
This will most likely make the whole platform more expensive, then if you would go with just a 6700K or 4790K.
Unless you would buy one decent gpu, and one realy cheap one.
But still i would go with the intel i7 route personaly.

2500k master race !

That would be, because there is no such thing as a free lunch.
Every instruction a processor can execute requires resources, so supporting more instructions leaves you with less resources for other things.

This is also the reason why Zen will not support several instruction set extensions Bulldozer supported.
Most of those instructions became redundant, when AMD was forced to implement the Intel equivalents, duo to code mostly targeting Intel instruction set extensions, thus leaving AMD implementing those instructions twice.
Obviously that's not efficient.

I've made the mistake before of buying an X99 motherboard without VT-d support before (it simply didn't have the toggle in the BIOS), however, I was able to return it.

This can be a massive pain in the ass for anyone looking to use certain extensions on consumer motherboards (even on Intel's enthusiast platform). Even after contacting the manufacturer's support before hand I had no response.

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Yeah, it can be a pain.

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Which motherboard was that?
Because i would like to research that.

MSI X99-A, the option just wasn't in BIOS.

Ah an Msi board, thank you.
i´m going to dig into this.

Most Asrock X99 boards do support it.
Asus X99 Deluxe does support is aswell.
i suppose that most other Asus X99 boards support it aswell.

I'm rocking an ASUS X99-S now, which has the option. Although I do like the ASUS UEFI, that MSI board is really solid for its price, other than the lack of VT-D. For example, it has a PS/2 port and the USB support seems a lot more solid.

Yeah the addition of ps2 is nice.
But i do have to say that the Asus X99-S is realy the better board,
wenn its comes to build quality over the Msi X99 entry boards like the X99A Sli plus, Raider, Krait or Gaming7.

The Asus X99-S is basicly the exact same board as the Deluxe.
But its just gimped down in terms of connectivity feutures.
It has the same bios, same vrm etc etc.
And yes vt-d support is there.

Asrock boards mostly all support vt-d aswell.

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mumble better be a better board for a ~£40 price bump for what seems like a better BIOS mumble