On Friday, April 6, 2018 at 9:27:11 PM UTC-4, Drew White wrote:
> On Saturday, 7 April 2018 10:41:13 UTC+10, Thierry Laurion  wrote:
> > You seem to have misunderstood. Ivy bridge and beyond on the Intel side 
> > will provide you with SLAT capabilities, IOMMU and virtualization, which is 
> > all that is required.  A x230 with 16gb ram and a i5 or i7 will provide you 
> > akk the power needed if you have an sad drive.
> I only went on what I was told. I have Ivy Bridge, and they don't have SLAT.

Which CPU in particular? Did you look it up at the following link?

> At least, they don't SAY they do.

Which "they" are we talking about? If you mean Intel, they are on top of 
keeping the ark pages updated with this information.
> Do they sometimes not say they have it even when they do?

I doubt it. But CPU-reporting tools might misreport information due to a bug, 
or might report how the BIOS has configured the CPU rather than what the CPU is 
capable of.

In addition to the CPU having to support certain features, many manufacturers 
don't enable the requisite virtualization features in the BIOS startup. 
Ignoring the closed-source firmware controversy (I don't want engage deeply on 
that, other than to say there are some complex ways of working around the BIOS 
issues with coreboot, etc. but there is no guarantee)...the BIOS issue is why I 
would recommend Thinkpad and Dell workstation-laptops from 2011 onward if the 
installed CPU has been verified in ARK* to have the supported features: VT-x 
with EPT or RVI *AND* VT-d or AMD-Vi aka IOMMU. These manufacturers went out of 
their way to do things correctly for their business-oriented machines, ensuring 
that all the higher-end CPU features could be utilized.

E.g. why the "manufactured after 20xx" approach does not work...

- I have a stack of purchased-used Thinkpad W520s here: manufactured in 2011 
and 2012, they meet the prerequisites, as they have Sandy Bridge CPUs and 
proper support in BIOS.

Sadly the embedded CPU in my GPX Pocket, manufactured in 2017, has an Atom 
x7-Z8750 (Cherry Trail family of power-efficient CPUs). While that CPU was 
released to market in 2016, and while it support VT-x, both EPT and VT-d are 
missing, so no QUBES 4.0 support. :(

Last caveat: some Intel CPUs had broken support for these features in early 
steppings (manufacturer run tweaks), e.g. this one, which did not support EPT 
until the C2 stepping: 


* AMD likely has a similar site to Intel's ARK site for use in gathering 
information on CPU features, but I haven't dug into that.

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