Is this Intel i7 machine good for LTSpice?

On a sunny day (Sun, 2 Nov 2014 12:09:54 -0800 (PST)) it happened Lasse
Langwadt Christensen <langwadt@fonz.dk> wrote in
<dc45b7d4-b977-43ae-bb08-63635c4739b2@googlegroups.com>:

>VGA is not much use, but unless you want to watch something from Hollywood=

VGA is still very useful,
I have one HD monitor with an extra VGA to a PC at the other side of the room.
Its faster than ssh -Y and does not load the network.
It displays lots of technical stuff that I run remote via wireless keyboard and mouse on that PC.

Den s=F8ndag den 2. november 2014 21.28.48 UTC+1 skrev Jan Panteltje:
> On a sunny day (Sun, 2 Nov 2014 12:09:54 -0800 (PST)) it happened Lasse
> Langwadt Christensen <langwadt@fonz.dk> wrote in
> <dc45b7d4-b977-43ae-bb08-63635c4739b2@googlegroups.com>:
>=20
> >VGA is not much use, but unless you want to watch something from Hollywo=
od=3D
>=20
> VGA is still very useful,
> I have one HD monitor with an extra VGA to a PC at the other side of the =
room.
> Its faster than ssh -Y and does not load the network.
> It displays lots of technical stuff that I run remote via wireless keyboa=
rd and mouse on that PC.

sure it is better than nothing, i.e. as an extra free input on a monitor=20
But if given a choice you wouldn't want to use VGA

-Lasse

On Sun, 02 Nov 2014 19:02:35 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

>On a sunny day (Sun, 02 Nov 2014 10:21:33 -0800) it happened John Larkin
><jlarkin@highlandtechnology.com> wrote in
><6erc5ahtpf0buuavb0fpbidbbeqi60v9r1@4ax.com>:
>
>>I'll have to tweak resistors and capacitors, and the cap values are
>>too big for variable capacitors. And, as noted, it would be hard to
>>instrument.
>>
>>Here's the current output when the load voltage steps from about 0.5
>>to 3 volts.
>>
>>>https://dl.dropboxusercontent.com/u/53724080/Circuits/Current_Sources/Hysterical_A1.jpg
>>
>>I want it as flat as possible.
>
>It looks a bit under-compensated, as if it takes time for it to respond to a load change.
>It can probably never be faster than the /\/\/ cycles, but should be possible bette rthan this.
>Diff part..

I'm switching at 1.5 MHz and I want constant current for load steps in
the picosecond time domain. 

>
>>The fast ripple is the basic 1.5 MHz switcher frequency. The various
>>whoopie-doos are from loop dynamics and the chain of progressively
>>smaller, bias-tee-like damped inductors between the switcher and the
>>load. The constant-current hysterical switcher is, natively, about 4
>>or so orders of magnitude too slow for my application.
>>
>>Everything interacts with everything else; it's like tuning a big LC
>>filter by hand, never a fun thing to do. Spice helps me acquire at
>>least some instincts for tuning. Maybe I can fix the cap values and
>>tune only resistors on the breadboard.
>>
>>Rob, one of my guys, has a fierce Linux computer just for sims and
>>FPGA compiles, and he knows how to do automatic iterative parts value
>>tweaking in a loop around Spice. Maybe he can set up the problem and
>>run it for a couple of days or weeks.
>>
>>I could probably step each of the six most important values, maybe 4
>>steps each, and pick the best waveform. That would be 4096 sims, about
>>60 hours of computing on my PC.
>
>
>I have never been a PID guy, really, I have a simlilar problem here with frequency stabilization.
>been testing large part of the day, reading many papers, got things working,
>got severely pissed with Analog Devices (they provide PLL calculation soft that refuses to run under Linux wine,
>even seems encryped, takes hour to un-encrypt, then cannot find DLLs), OK,
>then I decided to do it in all software and not buy their chip.
>I think the software solution can be better than their chip, anyways, experiment is fun :-)
>I have coded it, but really need to watch some movie to prevent electronics overdose.
>

The switcher is hysteretic, so there's no PID loop. Being hysteretic
means there's no loop compensation to get just-right, and it also
means that the switcher is fast and has no memory of the past; every
switch cycle stands on its own.

I tried a true hysteretic switcher: current sense resistor, diff gain,
schmitt comparator, mosfet driver. That works, but the frequency
varies all over the place, which has bad side effects. We had a
brainstorm meeting and came up with the hysterical converter. A dflop
drives the synchronous switching fets. We clock it ON at 1.5 MHz and
let the sense current resistor/amp/comparator clear it OFF when the
current hits the setpoint. That results in fixed-frequency PWM, but
with no PID or other memory in the loop. (I'm sure the idea has been
invented many times before.)

By moving a couple of wires, that can be converted to a first-order
delta-sigma loop. It's fun, but has a lot more current ripple than the
clocked hysterical converter.

The current-sense resistor has to be small to keep power dissipation
down, so we need a ton of differential gain, and there will be volts
of 1.5 MHz triangular common-mode junk on the resistor. A MiniCircuits
balun seems (in sim) to cut the common-mode noise down by about 20:1.

Like all RF folks, their parts are grossly underspecified. If you want
to know the winding and leakage inductances of their parts, you have
to measure them. RF is more like plumbing than engineering.

What, me ramble?


-- 

John Larkin         Highland Technology, Inc

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

On a sunny day (Sun, 02 Nov 2014 12:39:52 -0800) it happened John Larkin
<jlarkin@highlandtechnology.com> wrote in
<6b4d5al4b453j1af426p57gpspuvb3gagj@4ax.com>:

>On Sun, 02 Nov 2014 19:02:35 GMT, Jan Panteltje
><pNaonStpealmtje@yahoo.com> wrote:
>
>>On a sunny day (Sun, 02 Nov 2014 10:21:33 -0800) it happened John Larkin
>><jlarkin@highlandtechnology.com> wrote in
>><6erc5ahtpf0buuavb0fpbidbbeqi60v9r1@4ax.com>:
>>
>>>I'll have to tweak resistors and capacitors, and the cap values are
>>>too big for variable capacitors. And, as noted, it would be hard to
>>>instrument.
>>>
>>>Here's the current output when the load voltage steps from about 0.5
>>>to 3 volts.
>>>
>>>>https://dl.dropboxusercontent.com/u/53724080/Circuits/Current_Sources/Hysterical_A1.jpg
>>>
>>>I want it as flat as possible.
>>
>>It looks a bit under-compensated, as if it takes time for it to respond to a load change.
>>It can probably never be faster than the /\/\/ cycles, but should be possible bette rthan this.
>>Diff part..
>
>I'm switching at 1.5 MHz and I want constant current for load steps in
>the picosecond time domain. 

Yes, OK, then the switcher wil have to swicth off early, or you need to add some analog series regulator.




>>>The fast ripple is the basic 1.5 MHz switcher frequency. The various
>>>whoopie-doos are from loop dynamics and the chain of progressively
>>>smaller, bias-tee-like damped inductors between the switcher and the
>>>load. The constant-current hysterical switcher is, natively, about 4
>>>or so orders of magnitude too slow for my application.
>>>
>>>Everything interacts with everything else; it's like tuning a big LC
>>>filter by hand, never a fun thing to do. Spice helps me acquire at
>>>least some instincts for tuning. Maybe I can fix the cap values and
>>>tune only resistors on the breadboard.
>>>
>>>Rob, one of my guys, has a fierce Linux computer just for sims and
>>>FPGA compiles, and he knows how to do automatic iterative parts value
>>>tweaking in a loop around Spice. Maybe he can set up the problem and
>>>run it for a couple of days or weeks.
>>>
>>>I could probably step each of the six most important values, maybe 4
>>>steps each, and pick the best waveform. That would be 4096 sims, about
>>>60 hours of computing on my PC.
>>
>>
>>I have never been a PID guy, really, I have a simlilar problem here with frequency stabilization.
>>been testing large part of the day, reading many papers, got things working,
>>got severely pissed with Analog Devices (they provide PLL calculation soft that refuses to run under Linux wine,
>>even seems encryped, takes hour to un-encrypt, then cannot find DLLs), OK,
>>then I decided to do it in all software and not buy their chip.
>>I think the software solution can be better than their chip, anyways, experiment is fun :-)
>>I have coded it, but really need to watch some movie to prevent electronics overdose.
>>
>
>The switcher is hysteretic, so there's no PID loop. Being hysteretic
>means there's no loop compensation to get just-right, and it also
>means that the switcher is fast and has no memory of the past; every
>switch cycle stands on its own.

Yes, I have done that too...


>I tried a true hysteretic switcher: current sense resistor, diff gain,
>schmitt comparator, mosfet driver. That works, but the frequency
>varies all over the place, which has bad side effects. We had a
>brainstorm meeting and came up with the hysterical converter. A dflop
>drives the synchronous switching fets. We clock it ON at 1.5 MHz and
>let the sense current resistor/amp/comparator clear it OFF when the
>current hits the setpoint. That results in fixed-frequency PWM, but
>with no PID or other memory in the loop. (I'm sure the idea has been
>invented many times before.)

This is what I do here:
 http://panteltje.com/panteltje/pic/pwr_pic/
there is a current sense transformer, but also a current sense resistor that triggers a comparator
that switches of the MOSFET.
The problem is the energy in the inductors and capacitors will NOT suddenly disapear,
it takes time.
In the sixties I did that (much slower in those days) with an analog transistor series regulator after a thyristor switcher
where the thyristor switcher on average held the voltage over the series transistor as low as possible (just above the ripple)
that was for the telco here.
I dunno what you dissipation issues would be.

 


>By moving a couple of wires, that can be converted to a first-order
>delta-sigma loop. It's fun, but has a lot more current ripple than the
>clocked hysterical converter.
>
>The current-sense resistor has to be small to keep power dissipation
>down, so we need a ton of differential gain, and there will be volts
>of 1.5 MHz triangular common-mode junk on the resistor. A MiniCircuits
>balun seems (in sim) to cut the common-mode noise down by about 20:1.
>
>Like all RF folks, their parts are grossly underspecified. If you want
>to know the winding and leakage inductances of their parts, you have
>to measure them. RF is more like plumbing than engineering.
>
>What, me ramble?


Me too, I am watching 'red' with whatshisname.

On Sun, 2 Nov 2014 15:02:04 -0500, "Carl Ijames"
<carl.ijamesXX@XXverizon.net> wrote:

>"Joerg"  wrote in message news:cbn7m2Fla99U1@mid.individual.net...
>
>Joerg wrote:
>> Carl Ijames wrote:
>>> Don't know about computation speed, but this link says the video card 
>>> will
>>> drive 3 monitors:
>>> http://www.geforce.com/hardware/desktop-gpus/geforce-gt-720/specifications.
>>> Looking at Dell's site I don't see any mention of expansion slots, and
>>> looking at the one picture with the cover off I really can't see any 
>>> sockets
>>> beyond the video card, so if any further expansion is important you need 
>>> to
>>> ask Dell for clarification.
>>>
>>
>> Looks like you are right:
>>
>> http://www.dell.com/ed/business/p/xps-8700/pd
>> http://core0.staticworld.net/images/article/2013/07/1253541_sr-1160-100047019-orig.jpg
>> http://www.pcworld.com/article/2047487/dell-xps-8700-special-editions-review-a-little-less-performance-for-a-lot-less-cash.html
>>
>> Quote "There's only one PCIe x16 slot, which means you won't be able to
>> add a second video card to take advantage of Nvidia's SLI technology".
>>
>> No slots. There's one more card in the bottom, not sure what that is.
>> But if the video can drive three monitors it should be fine, I never
>> added any cards to my current PC either.
>>
>
>Only question is, how can one connect two regular OPC monitors to this?
>
>http://www.geforce.com/hardware/desktop-gpus/geforce-gt-720/product-images

DVI? You can get a Display port -> DVI adaptor. Dell sends them out
with their business laptops.

Cheers

On Sunday, November 2, 2014 7:21:33 PM UTC+1, John Larkin wrote:
> On Sun, 02 Nov 2014 16:21:32 GMT, Jan Panteltje
> <pNaonStpealmtje@yahoo.com> wrote:
>=20
> >On a sunny day (Sun, 02 Nov 2014 08:00:36 -0800) it happened John Larkin
> ><jlarkin@highlandtechnology.com> wrote in
> ><0nkc5aljhec5r36ptkoaqbt0a48ud2j5vo@4ax.com>:
> >
> >>On Sun, 02 Nov 2014 07:25:49 -0800, Joerg <news@analogconsultants.com>
> >>wrote:
> >>
> >>>Folks,
> >>>
> >>>Need to spiff up my simulation speeds here. IIRC Mike Engelhardt state=
d
> >>>that the Intel i7 is a really good processor for LTSPice. According to
> >>>this it looks like the 4790 is the fastest of the bunch:
> >>>
> >>>http://www.intel.com/content/www/us/en/processors/core/core-i7-process=
or.html
> >>>
> >>>So, what do thee say, is the computer in the Costco link below a good
> >>>deal for LTSpice purposes?
> >>>
> >>>http://www.costco.com/Dell-XPS-8700-Desktop-%7c-Intel-Core-i7-%7c-1GB-=
Graphics-%7c-Windows-7-Professional.product.100131208.html
> >>>
> >>>
> >>>It's also available without MS-Office Home & Student 2013 for $100 les=
s
> >>>but I found that OpenOffice isn't 100% compatible in the Excel area so
> >>>that sounds like an ok deal. My hope is that it can drive two 27"
> >>>monitors but I guess I can always add in another graphics card if not.
> >>>
> >>>Reason I am looking at these is that I absolutely positively do not wa=
nt
> >>>any computer with Windows 8 in here and unfortunately that's what many
> >>>others come with.
> >>
> >>I have spent too many hours this weekend tweaking the transient
> >>response of a semi-hysteretic (we call it "hysterical") switchmode
> >>constant-current source. There are about 8 interacting knobs to turn.
> >>At 30 seconds per run, understanding the interactions is impossible.
> >>
> >>I want sliders on each of the part values, and I want to see the
> >>waveforms change as I move the sliders, like they were trimpots on a
> >>breadboard and I was looking at a scope. I need maybe 500 times the
> >>compute power that I have now.
> >>
> >>Mike should code LT Spice to execute on a high-end video card.
> >
> >Maybe building the real thing with some pots?
>=20
> I am halfway through building a breadboard; I'll post pics. I'm after
> extreme broadband high impedance output, which is hard to measure on a
> breadboard; Spice lets me graph all sorts of currents and nodes, so
> it's the best platform for development.
>=20
>=20
> >But without some theory backing it up how would you know it always works=
?
>=20
> I'll have to simulate, and then test, the thing over a range of loads.
>=20
>=20
> >And with the theory you do not need the sliders.
>=20
> I don't have sufficient theoretical skills to tune this circuit. I'm
> not sure if anyone does.
>=20
> >
> >I do not see the need for insane speeds, I have used LTspice more than o=
ften
> >the last few days, running on an old Duron 950, fast enough.
> >maybe you guys are doing something wrong?
>=20
>=20
> At 30-50 seconds per run, iteration is slow. Worse, the time lag
> wrecks my ability to acquire intuition about what's going on.
>=20
>=20
> >:-)
> >
> >And it is always an approximation, build the real thing too,
> >needed tweaking with resistors in series, that is analog,
> >got some nice 25 turn Bourns trimpots from ebay.....
>=20
>=20
> I'll have to tweak resistors and capacitors, and the cap values are
> too big for variable capacitors. And, as noted, it would be hard to
> instrument.
>=20
> Here's the current output when the load voltage steps from about 0.5
> to 3 volts.
>=20
> >https://dl.dropboxusercontent.com/u/53724080/Circuits/Current_Sources/Hy=
sterical_A1.jpg
>=20
> I want it as flat as possible.
>=20
> The fast ripple is the basic 1.5 MHz switcher frequency. The various
> whoopie-doos are from loop dynamics and the chain of progressively
> smaller, bias-tee-like damped inductors between the switcher and the
> load. The constant-current hysterical switcher is, natively, about 4
> or so orders of magnitude too slow for my application.
>=20
> Everything interacts with everything else; it's like tuning a big LC
> filter by hand, never a fun thing to do. Spice helps me acquire at
> least some instincts for tuning. Maybe I can fix the cap values and
> tune only resistors on the breadboard.
>=20
> Rob, one of my guys, has a fierce Linux computer just for sims and
> FPGA compiles, and he knows how to do automatic iterative parts value
> tweaking in a loop around Spice. Maybe he can set up the problem and
> run it for a couple of days or weeks.
>=20
> I could probably step each of the six most important values, maybe 4
> steps each, and pick the best waveform. That would be 4096 sims, about
> 60 hours of computing on my PC.
>=20
Or just plug it into Orcad PSpice, which has an optimizer option, to fit th=
e response to whatever you need. Start simulation in the afternoon, drink b=
eer, and show up for the solution in the morning. Not very informative theo=
ry wise, but it get the job done

Cheers

Klaus

Den s=F8ndag den 2. november 2014 23.03.01 UTC+1 skrev Martin Riddle:
> On Sun, 2 Nov 2014 15:02:04 -0500, "Carl Ijames"
> <carl.ijamesXX@XXverizon.net> wrote:
>=20
> >"Joerg"  wrote in message news:cbn7m2Fla99U1@mid.individual.net...
> >
> >Joerg wrote:
> >> Carl Ijames wrote:
> >>> Don't know about computation speed, but this link says the video card=
=20
> >>> will
> >>> drive 3 monitors:
> >>> http://www.geforce.com/hardware/desktop-gpus/geforce-gt-720/specifica=
tions.
> >>> Looking at Dell's site I don't see any mention of expansion slots, an=
d
> >>> looking at the one picture with the cover off I really can't see any=
=20
> >>> sockets
> >>> beyond the video card, so if any further expansion is important you n=
eed=20
> >>> to
> >>> ask Dell for clarification.
> >>>
> >>
> >> Looks like you are right:
> >>
> >> http://www.dell.com/ed/business/p/xps-8700/pd
> >> http://core0.staticworld.net/images/article/2013/07/1253541_sr-1160-10=
0047019-orig.jpg
> >> http://www.pcworld.com/article/2047487/dell-xps-8700-special-editions-=
review-a-little-less-performance-for-a-lot-less-cash.html
> >>
> >> Quote "There's only one PCIe x16 slot, which means you won't be able t=
o
> >> add a second video card to take advantage of Nvidia's SLI technology".
> >>
> >> No slots. There's one more card in the bottom, not sure what that is.
> >> But if the video can drive three monitors it should be fine, I never
> >> added any cards to my current PC either.
> >>
> >
> >Only question is, how can one connect two regular OPC monitors to this?
> >
> >http://www.geforce.com/hardware/desktop-gpus/geforce-gt-720/product-imag=
es
>=20
> DVI? You can get a Display port -> DVI adaptor. Dell sends them out
> with their business laptops.
>=20
> Cheers

it is HDMI, apart from encryption and audio it is the same as DVI


-Lasse

On Sun, 02 Nov 2014 14:56:04 -0500, rickman <gnuarm@gmail.com> wrote:

>On 11/2/2014 12:53 PM, Joerg wrote:
>> Too much risk. I've heard that running legacy software is tough in Win-8
>> but Win-7 can mostly do it. Not as good as XP.

>What legacy software?  I have Windows 8 and I'm not having problems 
>running anything I ran on my old Vista laptop.

I recently awarded myself a short vacation in honor my burning a huge
amount of time getting old software to run nicely on Windoze 8.1.
Specifically, the DOS versions of various fiduciary programs dating
1996 through 2002, which the customer insisted had to run even though
later versions worked just fine.  The problem was that the tax rules
and tables all changed over the years and they wanted the original
versions.  I ended up running them under DOSbox, which was originally
designed to run ancient games, but works equally well with ancient
business applications:
<http://www.dosbox.com/status.php?show_status=1>
I also tried them under VMware and VirtualBox, both of which worked
nicely, but DOSbox is easier and faster.

Another horror was Office 2003 on Windoze 8.1.  It installs, updates,
loads, and looks like it might work, but eventually crashes.  All I
really needed was Outlook 2003, but that would hang after polling for
mail a few times.  I probably could have figured out the problem, but
convinced the customer that Mozilla Thunderbird would be a suitable
option.

Then, there's WordPerfect 12 which I think was introduced in 2002.
Amazingly, it worked 99%.  However, the 1% was fatal.  Windoze file
association would not start WP12 if I double clicked on a WPD file (or
any of the other WP files).  It took a while to figure out that WP12
was trying to use an ancient ODBC version, which required that WP12
beg permission of the Windoze security abomination before it would
condescend to even supply an error message.  Fixed by running WP12 as
administrator, which by passes most of the security mess.

I guess the moral here is to not try to run 12+ year old software on
Windoze 8.1.  My mistake was assuming that since all the
aforementioned software ran just fine in Windoze 7, the new and
improved Windoze 8.1 couldn't possibly break something that already
worked so well.

>>> One catch.  LTspice saves its preferences to:
>>>    C:\windows\scad3.ini
>>> which has to be writeable.  The fix is to use the
>>>    -ini <path>
>>> command line switch, which will:
>>>    Specify an .ini file to use other than %WINDIR%\scad3.ini
>>> <http://ltwiki.org/LTspiceHelp/LTspiceHelp/Command_Line_Switches.htm>

>I need to note this somewhere.  Writing to the Windows directory is a 
>*very* bad idea.

It was standard procedure in Windoze 3.1, where almost all
applications dropped pick_a_name.ini files in the C:\Windows\
directory.  I do have to admit it was handy as the files were easy to
find and save.  The new and improved versions of Windoze hide these
config files in either the registry, or bury them 5 directory layers
deep, where few can find them without specialized tools or inside
information.

>I can't tell you how many developers do all sorts of 
>things they aren't supposed to under windows.  That is the actual cause 
>of many problems people have running older software under Windows.  They 
>don't listen to the people providing them with the OS!

LTspice (aka SwitcherCAD) is a rather old program, with many of the
traditions of Windoze 3.1 still present.  If you don't like that, try
running some of the various NEC antenna modeling programs, that still
use the terms "card" and "deck" from the Hollerith punch card era. The
common mantra is the same everywhere... if it works, don't touch it.



Looking at the benchmarks at:
<http://fetting.se/images/PC%20Speed%20Benchmark%20running%20LTspice%20circuits.pdf>
my Dell Optiplex 755 clunker runs the 3 benchmarks at:
   14.5   7.6   3.6
If I upgrade to the fastest machine on the list:
    4.0   2.9   1.0
or roughly 3 times faster.  Might be worth $1200+. 

The database is at:
<https://groups.yahoo.com/neo/groups/LTspice/database/2/edit>
and shows no Windoze 8.1 benchmarks and no SSD, so those will remain
an unknown.  The benchmark files and instructions are at:
<https://groups.yahoo.com/neo/groups/LTspice/files/%20Examples/Benchmark/>
If you run the benchmark, be sure to add it to the database.



-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

On Sun, 02 Nov 2014 14:28:57 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:

>Looking at the benchmarks at:
><http://fetting.se/images/PC%20Speed%20Benchmark%20running%20LTspice%20circuits.pdf>
>my Dell Optiplex 755 clunker runs the 3 benchmarks at:
>   14.5   7.6   3.6
>If I upgrade to the fastest machine on the list:
>    4.0   2.9   1.0
>or roughly 3 times faster.  Might be worth $1200+. 

I ran the benchmarks on my Dell Optiplex 960 (XP-SP3, E8500 3.2GHz,
4GB RAM, 1TB drive).
    10.0  11.2   2.5
So, $1200 will get me about 2.5 times faster (ignoring some kind of
problem with the Mic2 test).

>The database is at:
><https://groups.yahoo.com/neo/groups/LTspice/database/2/edit>
>and shows no Windoze 8.1 benchmarks and no SSD, so those will remain
>an unknown.  The benchmark files and instructions are at:
><https://groups.yahoo.com/neo/groups/LTspice/files/%20Examples/Benchmark/>
>If you run the benchmark, be sure to add it to the database.

-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

On Sun, 02 Nov 2014 12:27:52 -0800, DecadentLinuxUserNumeroUno
<DLU1@DecadentLinuxUser.org> wrote:

>  Even better than those are the mSATA drives and now, the best...  the
>M.2 drives.
>  Not much bigger than a couple of air mail stamps (I date myself).
>  Way faster than the 2.5" form factor SSD "laptop drive" replacement
>family.

The SSD drive I recommended comes in both SATA3 and mSATA
configurations:
<http://www.samsung.com/global/business/semiconductor/minisite/SSD/global/html/ssd840evo/overview_mSATA.html>
<http://www.samsung.com/global/business/semiconductor/minisite/SSD/global/html/ssd840evo/overview.html>
The specs look fairly close:
<http://www.samsung.com/global/business/semiconductor/minisite/SSD/global/html/ssd840evo/specifications.html>

I have an older mSATA drive in my Acer C720 running Linux.  Very very
very very fast, but I haven't compared it with a SATA3 drive.

-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558