Is this Intel i7 machine good for LTSpice?

Lasse Langwadt Christensen wrote:
> Den s�ndag den 2. november 2014 18.24.23 UTC+1 skrev Joerg:
>> 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
>>
> 
> I'd expect that you can connect a monitor to each of the three outputs, 
> VGA,DVI,HDMI. I have an old geforce and that's how that works
> 
> VGA is not much use, but unless you want to watch something from Hollywood 
> DVI and HDMI is the same thing
> 

I do a lot of video conferencing via web where content moves. Other than
that just CAD, no movie streaming and such.

-- 
Regards, Joerg

http://www.analogconsultants.com/

Phil Hobbs wrote:
> On 11/2/2014 12:31 PM, Joerg wrote:
>> Phil Hobbs wrote:
>>> On 11/2/2014 11:00 AM, John Larkin wrote:
>>>> 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
>>>>> stated
>>>>> 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-processor.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
>>>>> less
>>>>> 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
>>>>> want
>>>>> 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.
>>>>
>>>>
>>>
>>> You can go quite a bit faster with a nice multicore machine--LTspice
>>> lets you choose how many threads to run.  My desktop machine (about 3
>>> years old now) runs about 150 Gflops peak.  Supermicro is an excellent
>>> vendor.
>>>
>>
>> But they should work on their web site some more or get rid of scripting
>> or whatever. Other than a language selector it shows ... nothing.
>>
> Probably a NoScript issue, or something like that. 


Why on earth can't web designers figure out the feedback thing. Like
when a script won't excecute show a warning about it.


>                                      ... Talk to Alexander at
> alvio.com a primo Supermicro reseller, and tell him "Hi" from me.
> 

Their site is a bit weird as well. On some lines you can select
components but, for example, not the version of i& processor or the monitor:

http://www.alvio.com/config.aspx?t=&product_ID=111084

-- 
Regards, Joerg

http://www.analogconsultants.com/

miso wrote:
> Joerg wrote:
> 
>> There are so many variants of graphics cards that it would require tons
>> of work for Mike's team.
>>
> 
> It isn't the graphics card as much as the standard of acceleration. ATI and 
> Nvidia use different standards.
> 
> NGspice has Cuda support, which means you need Nvidia.
>> http://ngspice.sourceforge.net/
> 
> You also need an OS that supports CUDA.
> 

That's where it becomes esoteric to me. I just want to install LTSpice
and ... simulate. Not get into the business of IT and computer science
which is pretty foreign to us analog guys anyhow.

-- 
Regards, Joerg

http://www.analogconsultants.com/

Klaus Kragelund wrote:
> I have a two year old laptop. I was tired with the slow startup of
> programs, so I replaced the hard disk with a SSD. Amazing difference
> in speed. As far as I can see also for the simulations although I did
> not do a benchmark test.
> 
> The Kingston SSD came with a USB connected enclosure to mount the old
> hard disk in, so the harrdisk was mirrored and no re install of
> programs was needed
> 

That's what some folks in Germany said as well. Although I don't know
why because if you had a machine with, say, 32GB of RAM then everything
and the kitchen sink will comfortably fit into that much RAM and should
execute even faster than via SSD.

-- 
Regards, Joerg

http://www.analogconsultants.com/

Jeff Liebermann wrote:
> On Sun, 02 Nov 2014 09:53:42 -0800, Joerg <news@analogconsultants.com>
> wrote:
> 
>> Any guess how long MS will support Win-7?
> 
> Jan 13, 2015
> <http://windows.microsoft.com/en-us/windows/lifecycle>
> Extended support means that MS will gladly continue supporting Windoze
> 7 if you throw money at them.  MS is following the Apple policy of
> killing everything that's more than 5 years old (except in California,
> which is 7 years):
> <http://support.apple.com/en-us/ht1752>
> 
>> When it comes to PCs I am lazy :-)
> 
> That's why I'm still in business to seperate such customers from their
> money.  Lazy is good for supporting my decadent and lavish lifestyle.
> 
>> I just want to plug it in and go. Re-installing all my stuff takes
>> enough time already.
> 
> It's fairly easy to migrate programs and data from most anything to
> Windoze 7.
> <http://www.dummies.com/how-to/content/how-to-use-easy-transfer-in-windows-7.html>
> <http://windows.microsoft.com/en-us/windows7/products/features/windows-easy-transfer>
> However, Easy Transfer disappeared in Windoze 8.1, so you're either on
> your own or purchase a 3rd part program to do the dirty work.
> 

Well, I do want to update a lot of the software to newer versions and
also I do not trsut auto-installers.


>>> Before buying anything, I suggest you try LTspice on the new machine.
>>> This is VERY easy with LTspice which doesn't use the registry or
>>> require admin rights.  Just copy the files to a flash drive and it
>>> should work.  
>> I am quite sure Costco will not let me do this :-)
> 
> It's easier to obtain forgiveness than permission.
> 
> Are you really going to spend $1,300+ for a new machine without even a
> test drive? ...


Done it before, worked every time.


>    ... Costco has a very good return policy, but you still have
> to haul it home, get it running, update, tweak, tune, and then try. If
> unacceptable, you get to try and fit everything back into the original
> box (which never seems to fit).  This is not being lazy.
> 

Ok, but for example a gamer machine like the XPS series is a pretty good
bet that it'll perform well with SPICE.

-- 
Regards, Joerg

http://www.analogconsultants.com/

rickman wrote:
> On 11/2/2014 12:53 PM, Joerg wrote:
>> Jeff Liebermann wrote:
>>> On Sun, 02 Nov 2014 07:25:49 -0800, Joerg <news@analogconsultants.com>
>>> wrote:
>>>
>>> LTspice benchmark on various machines:
>>> <http://fetting.se/images/PC%20Speed%20Benchmark%20running%20LTspice%20circuits.pdf>
>>>
>>>
>>>> Reason I am looking at these is that I absolutely positively do not
>>>> want
>>>> any computer with Windows 8 in here and unfortunately that's what many
>>>> others come with.
>>>
>>> Windoze 8.1 can be made semi-tolerable by putting the start menu back
>>> in and making it look like Windoze 7.
>>> <http://www.classicshell.net>
>>> I've been installing it on all my customers Windoze 8.1 machines and
>>> have had no complaints or problems.  If you like wiggly icons on the
>>> Windoze 8.1 start screen, you can do <Shift><Start>.
>>>
>>
>> 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.
> 

Ahm, my SW goes back to the mid-80's. Unorthodox filter design,
beamfield simulators and such.

> 
>> When it comes to PCs I am lazy :-)
>>
>> I just want to plug it in and go. Re-installing all my stuff takes
>> enough time already.
> 
> I hear you.  The big problem I had with setting up my Win 8 laptop was
> that a lot of the freeware has become burdened with ads, toolbars and
> other malware to the point I'm not willing to use it.
> 

Yes, nagware is a major problem. It already was 10 years ago where it
took a lot of effort to rid the computer of that.

> 
>>> Before buying anything, I suggest you try LTspice on the new machine.
>>> This is VERY easy with LTspice which doesn't use the registry or
>>> require admin rights.  Just copy the files to a flash drive and it
>>> should work.
>>
>> I am quite sure Costco will not let me do this :-)
> 
> You can try finding the computer salesperson in the store.  They are
> limited by store policy of course, but I have met a few who were very
> willing to help as best they could.
> 

They only have them online.

> 
>>> 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.  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!
> 

I install everything in my own directory called "Programs". That avoids
a lot of such issues. Makes it tough in a multi-user environment but I
work alone here.

-- 
Regards, Joerg

http://www.analogconsultants.com/

Den mandag den 3. november 2014 21.20.35 UTC+1 skrev Joerg:
> Lasse Langwadt Christensen wrote:
> > Den s=F8ndag den 2. november 2014 18.24.23 UTC+1 skrev Joerg:
> >> Joerg wrote:
> >>> Carl Ijames wrote:
> >>>> Don't know about computation speed, but this link says the video car=
d will=20
> >>>> drive 3 monitors:=20
> >>>> http://www.geforce.com/hardware/desktop-gpus/geforce-gt-720/specific=
ations.=20
> >>>> Looking at Dell's site I don't see any mention of expansion slots, a=
nd=20
> >>>> looking at the one picture with the cover off I really can't see any=
 sockets=20
> >>>> beyond the video card, so if any further expansion is important you =
need to=20
> >>>> 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-1160-1=
00047019-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-im=
ages
> >>
> >=20
> > I'd expect that you can connect a monitor to each of the three outputs,=
=20
> > VGA,DVI,HDMI. I have an old geforce and that's how that works
> >=20
> > VGA is not much use, but unless you want to watch something from Hollyw=
ood=20
> > DVI and HDMI is the same thing
> >=20
>=20
> I do a lot of video conferencing via web where content moves. Other than
> that just CAD, no movie streaming and such.
>=20

Then DVI will works just fine, HDMI is just DVI with optional audio and the=
 encryption Hollywood insists on if you bought a blueray movie

So just plug a monitor into both the HDMI and DVI output

-Lasse

rickman wrote:
> On 11/2/2014 10:25 AM, Joerg wrote:
>> Folks,
>>
>> Need to spiff up my simulation speeds here. IIRC Mike Engelhardt stated
>> 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-processor.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
>>
> 
> Hard to say.  The devil is in the details.  I have an i7 and I'm not
> convinced it is much better if any than other CPUs for most tasks.  One
> problem with the quad core is that that each core still runs at the same
> speed as a dual core or even slower due to the contention for memory
> bandwidth.  That is why I got a laptop with separate graphic memory. But
> overall I don't see big speed improvements.  I'd be willing to bet you
> won't see a huge difference between this machine and one costing a few
> hundred dollars less.  BTW, do you really need a new monitor?  I expect
> you can save a couple hundred more by getting a unit without monitor.
> 

That's just it, the price differential for the monitor is only $100.
Bought separately they are >$250. I could use it for a dual-monitor
setup. Two 27-inchers would allow me to have module spec, schematic,
layout and Digikey page in view simultaneously.

> 
>> It's also available without MS-Office Home & Student 2013 for $100 less
>> 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.
> 
> I use LibreOffice which is the same package from the developers who
> jumped ship at Oracle to continue development of OpenOffice the way they
> think is best.  I don't see compatibility issues and 90% of what I use
> office for is the spreadsheet.
> 

I've seen lots of issues, mostly with Excel. No VBA, x-axis in plots
gets crunched into oblivion and so on. Not too often but enough that I'd
be willing to spend the $100 for the MS-Office suite. Of course my
default Office package will be OO.

> 
>> Reason I am looking at these is that I absolutely positively do not want
>> any computer with Windows 8 in here and unfortunately that's what many
>> others come with.
> 
> Get something tailor made.  You can get both the best machine and the
> cheapest that way.  After all, they are all made from the same parts. It
> is just a question of who puts them together.
> 

Got to find a local place for that. Or I could use Phil Hoobs' supplier
over the web because he said they are good.

-- 
Regards, Joerg

http://www.analogconsultants.com/

upsidedown@downunder.com wrote:
> On Sun, 02 Nov 2014 07:25:49 -0800, Joerg <news@analogconsultants.com>
> wrote:
> 
>> Need to spiff up my simulation speeds here. IIRC Mike Engelhardt stated
>> 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-processor.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
> 
> How well does LTSpice spread simulation cycles between multiple
> processors and multiple cores (Hyperthreading etc.) ?
> 

Supposedly quite well but I am new to this, so I don't have any
experience. Once we did a crude benchmarking and a guy with a quad-core
ran my sim more than 3x faster. Heck, I'd plunk down money even for 1.5x.

-- 
Regards, Joerg

http://www.analogconsultants.com/

DecadentLinuxUserNumeroUno wrote:
> On Sun, 02 Nov 2014 07:25:49 -0800, Joerg <news@analogconsultants.com>
> Gave us:
> 
>> Need to spiff up my simulation speeds here. IIRC Mike Engelhardt stated
>> 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-processor.html
> 
>   That actually looks like a really nice deal.  You can't go wrong.


Thanks, good to know.


> Mine cost me $2500 and took over a year to build as budgets tightened.
> 
>  I'll bet my 3930K beats it though.
> 
>   The newer fabs have higher GHz rates, but are not as fast as their
> first series were, which the smaller fabs replaced..
> 
>   I have 6x2 cores, and I don't even know if they do that any more
> except on Xeons.
> 
>   I scream past all the benchmarks.  Two more cores really makes a
> difference.  I beat machines pegging faster raw "speeds" all the time.
> Mainly because they only have 4x2 cores.
> 
>   Not cheap.  The i7-3930K was $695, and the X79 Mobo under it was $400.
> The 32GB RAM was not cheap either for 2133MHz, And that was before the
> 2400MHz stuff appeared.  I can still upgrade the GPU and the RAM and get
> even faster.
> 

The Costco machines have 1600MHz RAM so that might put a slight crimp
into things.


>   Since I cannot afford to put $1000 into a Titan video card, I miss on
> a few benchmarks with my $250 GTX650.


I am not at all concerned about video because that's just used for
static display and sometimes video conferencing. No games, no movies.

-- 
Regards, Joerg

http://www.analogconsultants.com/