Re: [CAD_CAM_EDM_DRO] Re: LinuxCNC laptops - OT Compaq

Compaq = Gorgeous, reliable, well engineered - yes. Very Nice.
But WAY overpriced (in Europe= no discounts).
Poor bang for the buck.
And silly problems like the cd you mentioned, just like old ibm stuff.
And SUN solaris stuff (the big ones).

NEVER buy Compaq stuff like that. Thats why they tanked, just like the
old ibm (who don´t do the silly games any more).

(Oh, I sold 1/3 the internet in Finland and 8% in Spain, and managed 70
servers (and 500 routers) 24x7 and was tech mgr for nr 4 pc store in
Finland, so I have plenty of experience in this stuff).

For reliable laptops in general, today, buy asus or something similar.
Excellent engineering, no frills, no games with hw and similar.

Acer may be ok. HP is very suspect. DELL likewise.

AND before everyone flames me with the "..my [mark] never has problems
..." these are based on real-world results.
Whats your maintenance cost in work hours / 100 laptops ?

And if you only have one, and spent 30 hours getting it to run right
(display driver issues, how is your sleep mode, does the touchpad work,
and the usb, ... ) at 30$ / hour it was pretty expensive. For 100
laptops its a disaster (and about average in any general organisation I
know of).

</RANT>

Dave Halliday wrote:

> Drifting a bit off-topic here but if you think Compaq laptops and Desktops
> are a bother, check out their Servers.
>
> Gorgeous machines, bulletproof, very high performance and incredible bang
> for the buck (I worked with a lot of them about eight to twelve years ago)
>
> In order to make any and I do mean __any__ changes to the configuration, you
> had to have a proprietary CD-ROM disk for that model of machine.
>
> No disk + hardware change = bricked machine until you could get a
> replacement disk and reformat.
>
> Change RAM, add another HD - you needed that disk.
>
> They used to be available for free download but now they are available only
> as a part (re: $$$) and the older ones are no longer available.
>
> If you ever get the chance to buy a Compaq server on eBay or wherever, you
> will not be dissapointed but it needs to come with that CD-ROM.
>
> Dave
> (who owns and loves three Compaq 1850Rs)
>
>
>
>
>> -----Original Message-----
>> From: CAD_CAM_EDM_DRO@yahoogroups.com
>> [mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of Yahoo
>> Sent: Tuesday, March 04, 2008 7:52 AM
>> To: CAD_CAM_EDM_DRO@yahoogroups.com
>> Subject: [CAD_CAM_EDM_DRO] Re: LinuxCNC laptops
>>
>> I used to work at Intel, and I still know people who work at
>> Intel, and I
>> can tell you this kind of problem continues to get worse. The
>> good news is,
>> with higher processor speeds the system management tasks take
>> less time. The
>> bad news is, laptop makers continue to get more and more
>> proprietary in
>> their designs. You may have noticed that laptops almost
>> always ship with a
>> "special" version of Windows. I once had a Compaq laptop that
>> wouldn't work
>> any more if you formatted the hard drive. (Of course they did
>> that with
>> their desktops as well, but we all know what happened to
>> Compaq.) Add to
>> that VMX from Intel and SVM from AMD, and the target keeps
>> moving. Bottom
>> line is you never know until you try, and laptops are most
>> likely to have
>> problems with any real-time application because they were not
>> made for that.
>> Not that PCs were made for that either. The days when all PCs
>> conformed to
>> the IBM PC/AT specification are long gone.
>> --
>> Phil Mattison
>> http://www.ohmikron.com/
>> Motors::Drivers::Controllers::Software
>>
>> ----- Original Message -----
>> From: Stephen Wille Padnos <spadnos@...>
>> To: <CAD_CAM_EDM_DRO@yahoogroups.com>
>> Sent: Monday, March 03, 2008 8:18 PM
>> Subject: Re: [CAD_CAM_EDM_DRO] LinuxCNC laptops
>>
>>
>>
>>> Hi there.
>>>
>>> (I'm not sure if you're the same person who asked this
>>>
>> question on the
>>
>>> EMC-users list, but just in case you're not, here goes ... )
>>>
>>> Laptops are particularly susceptible to having problems due to power
>>> management. Intel built a special mode into their
>>>
>> processors, starting
>>
>>> somewhere in the 386/486 release cycle. It's called SMM or System
>>> Management Mode. The SMI interrupt is what puts the
>>>
>> processor into this
>>
>>> mode, and that interrupt can't be turned off. (even though some
>>> chipsets may allow it to be turned off, this is actually
>>>
>> out of spec for
>>
>>> the chip since thermal management is done in this mode, among other
>>>
>> things)
>>
>>> So here's the problem: every 64 seconds, and whenever a "system
>>> management event" occurs, the processor will stop whatever
>>>
>> it's doing,
>>
>>> and go off to take care of "system-y things". This can take several
>>> hundred milliseconds to complete. I'm not sure why it's so slow,
>>> considering that 300ms is about a billion cycles these
>>>
>> days, but that's
>>
>>> the kind of latency we've measured. If this happens when
>>>
>> you're trying
>>
>>> to output steps at a rate of 15 KHz, the step stream will
>>>
>> suddenly stop
>>
>>> (no deceleration) and then start up again a while later (with no
>>> acceleration), which is likely to cause the motors to
>>>
>> stall, or at least
>>
>>> to lose steps.
>>>
>>> This isn't a problem with EMC2 specifically, it should
>>>
>> happen to other
>>
>>> programs as well, including Mach3 (due to Windows), and
>>>
>> possibly even
>>
>>> TurboCNC (since SMI is supposed to be enabled by default).
>>>
>> Sometimes
>>
>>> you can get acceptable performance by tweaking the BIOS and
>>>
>> testing (a
>>
>>> lot). I don't know of any solutions that "just work",
>>>
>> especially for
>>
>>> many different CPUs and chipsets. If anyone has a good, general
>>> solution (for Windows or for Linux), I'd like to hear about
>>>
>> it so we can
>>
>>> incorporate it into EMC2.
>>>
>>> There are sometimes other problems with latops as well, such as
>>> insufficient drive strength from the parallel port, or no
>>>
>> parallel port
>>
>>> at all :)
>>>
>>> - Steve
>>>
>>> marcin_ose wrote:
>>>
>>>
>>>> Dear Group,
>>>>
>>>> Can you suggest what brands of laptops have good compatibility with
>>>> LinuxCNC, and what distribution of Linux you would recommend? I'm
>>>> looking for a laptop, and want to make sure that it will work well
>>>> with LinuxCAD for an CNC acetylene torch table that we're building.
>>>>
>>>> Thanks,
>>>>
>>>> Marcin
>>>>