RE: [CentOS] 12V computing?

2008-04-15 Thread Jason Pyeron
Thanks every one for putting so much effort in your responses, we have
ordered one to test with.

Fwiw, why it is 12V and using other voltages was way off topic. We are using
12V due to interoperability requirements. The environment it is going into
has on pair of redundant line to 12V power supplies and an internal battery
backup. There all other internal components operating at this 12V level.
That being said, we are trying to reduce the current draw of every device
vs. production and development costs (nice parametric equation in excel...).

Lastly, every piece of compiled by us goes through extra certification
(certify source, dev, test, production binaries = $$$), so we are not going
to recompile the kernel, and that is why we choose RHEL/Centos, as they are
binary compatible and reviewed.

-Jason Pyeron


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 -Original Message-
 From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
 Behalf Of Daniel de Kok
 Sent: Monday, April 14, 2008 3:02 AM
 To: CentOS mailing list
 Subject: Re: [CentOS] 12V computing?
 
 On Sat, Apr 12, 2008 at 12:16 AM, John R Pierce [EMAIL PROTECTED]
 wrote:
  Ben Gore wrote:
 
   I have run CentOS 4.5 on this platform without problems.
  
   I wouldn't expect any issues with CentOS 5+.
  
 
   are these Via C7 processors i686 compliant?
 
 Yes they are. Everything from the Nehemiah and newer cores.
 
 -- Daniel
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Re: [CentOS] 12V computing?

2008-04-14 Thread Daniel de Kok
On Sat, Apr 12, 2008 at 12:16 AM, John R Pierce [EMAIL PROTECTED] wrote:
 Ben Gore wrote:

  I have run CentOS 4.5 on this platform without problems.
 
  I wouldn't expect any issues with CentOS 5+.
 

  are these Via C7 processors i686 compliant?

Yes they are. Everything from the Nehemiah and newer cores.

-- Daniel
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RE: [CentOS] 12V computing?

2008-04-11 Thread Jason Pyeron

Any ideas if this can run centos with out a special modifications?

Elite C7VCM Mini-ITX Motherboard with VIA C7 1.5GHz Processor

http://resources.mini-box.com/online/MBD-E-C7VCM/MBD-E-C7VCM-manual.pdf

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 -Original Message-
 From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
 Behalf Of Jason Pyeron
 Sent: Thursday, April 10, 2008 1:43 PM
 To: 'CentOS mailing list'
 Subject: [CentOS] 12V computing?
 
 Does anyone on the list have recommendations on 12VDC based hardware which
 runs a stock Centos 4 (or even 5)?
 
 
 
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Re: [CentOS] 12V computing?

2008-04-11 Thread Gordon McLellan
Jason,

I don't see why the 32 bit version of centos would not run on that
hardware.   Despite the fancy processor name, it still has to work
with the i586 command set (at the worst).

There's no such thing as a 12 volt computer... unless you're looking
at some sort of weird industrial setup.  That motherboard runs of a
standard ATX power supply just like any other beige/black box would.
You can buy special electronic power supplies which convert 12V dc to
the ATX standard, these are often used for putting a computer in a
car.  Search the mini-box site for pico psu

Gordon

On Fri, Apr 11, 2008 at 2:29 PM, Jason Pyeron [EMAIL PROTECTED] wrote:

  Any ideas if this can run centos with out a special modifications?

  Elite C7VCM Mini-ITX Motherboard with VIA C7 1.5GHz Processor

  http://resources.mini-box.com/online/MBD-E-C7VCM/MBD-E-C7VCM-manual.pdf


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  -Original Message-
   From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
   Behalf Of Jason Pyeron
   Sent: Thursday, April 10, 2008 1:43 PM
   To: 'CentOS mailing list'
   Subject: [CentOS] 12V computing?
  
   Does anyone on the list have recommendations on 12VDC based hardware which
   runs a stock Centos 4 (or even 5)?
  
  
  
   -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
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RE: [CentOS] 12V computing?

2008-04-11 Thread Jason Pyeron


 -Original Message-
 From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
 Behalf Of Gordon McLellan
 Sent: Friday, April 11, 2008 4:10 PM 
 ...
 There's no such thing as a 12 volt computer... unless you're looking
 at some sort of weird industrial setup.  

Yes. We are trying to minimize costs  ( certification of deviation from
baseline centos/RHEL vs. hardware costs) in a 12VDC only environment.

 That motherboard runs of a
 standard ATX power supply just like any other beige/black box would.

The documents I have read disagree. See the picture too:

http://resources.mini-box.com/online/MBD-E-C7VCM/moreimages/image2.jpg


notice the modified ATX connector to only have +12 and ground.

 You can buy special electronic power supplies which convert 12V dc to
 the ATX standard, these are often used for putting a computer in a
 car.  

We are aware of these, but that would be just another part at another cost,
and another testing point, ...

 Search the mini-box site for pico psu
 
 Gordon
 
 On Fri, Apr 11, 2008 at 2:29 PM, Jason Pyeron [EMAIL PROTECTED] wrote:
 
   Any ideas if this can run centos with out a special modifications?
 
   Elite C7VCM Mini-ITX Motherboard with VIA C7 1.5GHz Processor
 
   http://resources.mini-box.com/online/MBD-E-C7VCM/MBD-E-C7VCM-manual.pdf
 
 
   -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
   -   -
   - Jason Pyeron  PD Inc. http://www.pdinc.us -
   - Principal Consultant  10 West 24th Street #100-
   - +1 (443) 269-1555 x333Baltimore, Maryland 21218   -
   -   -
   -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 
   This message is for the designated recipient only and may contain
   privileged, proprietary, or otherwise private information. If you
   have received it in error, purge the message from your system and
   notify the sender immediately.  Any other use of the email by you
   is prohibited.
 
 
 
 
   -Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Jason Pyeron
Sent: Thursday, April 10, 2008 1:43 PM
To: 'CentOS mailing list'
Subject: [CentOS] 12V computing?
   
Does anyone on the list have recommendations on 12VDC based hardware
 which
runs a stock Centos 4 (or even 5)?
   
   
   
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-   -
- Jason Pyeron  PD Inc. http://www.pdinc.us -
- Principal Consultant  10 West 24th Street #100-
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Re: [CentOS] 12V computing?

2008-04-11 Thread Ben Gore

I have run CentOS 4.5 on this platform without problems.

I wouldn't expect any issues with CentOS 5+.

-Ben


Jason Pyeron wrote:

Any ideas if this can run centos with out a special modifications?

Elite C7VCM Mini-ITX Motherboard with VIA C7 1.5GHz Processor

http://resources.mini-box.com/online/MBD-E-C7VCM/MBD-E-C7VCM-manual.pdf

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-   -
- Jason Pyeron  PD Inc. http://www.pdinc.us -
- Principal Consultant  10 West 24th Street #100-
- +1 (443) 269-1555 x333Baltimore, Maryland 21218   -
-   -
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This message is for the designated recipient only and may contain

privileged, proprietary, or otherwise private information. If you
have received it in error, purge the message from your system and
notify the sender immediately.  Any other use of the email by you
is prohibited. 
 

  

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Jason Pyeron
Sent: Thursday, April 10, 2008 1:43 PM
To: 'CentOS mailing list'
Subject: [CentOS] 12V computing?

Does anyone on the list have recommendations on 12VDC based hardware which
runs a stock Centos 4 (or even 5)?



-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
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- Jason Pyeron  PD Inc. http://www.pdinc.us -
- Principal Consultant  10 West 24th Street #100-
- +1 (443) 269-1555 x333Baltimore, Maryland 21218   -
-   -
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RE: [CentOS] 12V computing?

2008-04-11 Thread Jason Pyeron


 -Original Message-
 From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
 Behalf Of John R Pierce
 Sent: Friday, April 11, 2008 4:55 PM
 To: CentOS mailing list
 Subject: Re: [CentOS] 12V computing?
 
 Jason Pyeron wrote:
  Yes. We are trying to minimize costs  ( certification of deviation from
  baseline centos/RHEL vs. hardware costs) in a 12VDC only environment.
 
 
 by 12VDC, do you mean regulated 12VDC +/- xx%, or vehicular 12V which
 typically is 11-14V, and should be engineered to not burn up on 9-18V
 with noisy spikes et al?
 

We will have a regulator.

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Re: [CentOS] 12V computing?

2008-04-11 Thread Gordon McLellan
If you want to minimize power costs, look to higher voltage, not
lower.   Run your computers off 208-240 volts instead of 100-120.  If
your supply is not auto ranging, make sure it's set to the high / 230
setting.

Having a massive 12v power supply to run several computers isn't going
to save any power.  Your second picture just demonstrates they have
integrated the electronic power supply into the board, thus when your
power supply fails, you can replace the entire system instead of just
a component. It is doubtable than a 12VDC to ATX converter is any more
efficient than an AC-line to ATX converter.  Plus the cabling to
transfer 12V at 10a+ more than a few feet is going to be massively
expensive - look up the I2R losses on google.

In regards to cpu support, the via website mentions the C7 compares
directly with the Pentium IV, which would make it a 686 class cpu.
Additionally, they claim support for these extended instruction sets:
MMX, SSE, SSE2  SSE3

One thing you might want to consider, is DIY blade computing.  With
some clever wiring, you can splice the ATX connector harnesses from
several dead power supplies onto a modern high wattage psu, providing
power for 4 to 6 low-end system boards arranged in a stack.  A new 80
PLUS rated 500-600w psu should have no problems.  Pick one from the
stack to be the 'master', and toss a hard drive on it, the rest can
net boot from it.

Gordon
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Re: [CentOS] 12V computing?

2008-04-11 Thread jim

   there are computer systems that take 12VDC 
(for example the PC-104 type and others). such 
a computer system is a box that has a connection 
for 12VDC. inside the box is a power supply that 
takes the 12VDC and presents the +12VDC, -12VCD, 
5VDC, and -5VDC that's needed by the various 
electronic subsystems that make up the computer. 
   the installation of linux (or any other OS) 
is independent of the power requirements of the 
computer system. 


On Fri, 2008-04-11 at 16:09 -0400, Gordon McLellan wrote:
 Jason,
 
 I don't see why the 32 bit version of centos would not run on that
 hardware.   Despite the fancy processor name, it still has to work
 with the i586 command set (at the worst).
 
 There's no such thing as a 12 volt computer... unless you're looking
 at some sort of weird industrial setup.  That motherboard runs of a
 standard ATX power supply just like any other beige/black box would.
 You can buy special electronic power supplies which convert 12V dc to
 the ATX standard, these are often used for putting a computer in a
 car.  Search the mini-box site for pico psu
 
 Gordon
 
 On Fri, Apr 11, 2008 at 2:29 PM, Jason Pyeron [EMAIL PROTECTED] wrote:
 
   Any ideas if this can run centos with out a special modifications?
 
   Elite C7VCM Mini-ITX Motherboard with VIA C7 1.5GHz Processor
 
   http://resources.mini-box.com/online/MBD-E-C7VCM/MBD-E-C7VCM-manual.pdf
 
 
   -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
   -   -
   - Jason Pyeron  PD Inc. http://www.pdinc.us -
   - Principal Consultant  10 West 24th Street #100-
   - +1 (443) 269-1555 x333Baltimore, Maryland 21218   -
   -   -
   -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 
   This message is for the designated recipient only and may contain
   privileged, proprietary, or otherwise private information. If you
   have received it in error, purge the message from your system and
   notify the sender immediately.  Any other use of the email by you
   is prohibited.
 
 
 
 
   -Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Jason Pyeron
Sent: Thursday, April 10, 2008 1:43 PM
To: 'CentOS mailing list'
Subject: [CentOS] 12V computing?
   
Does anyone on the list have recommendations on 12VDC based hardware 
  which
runs a stock Centos 4 (or even 5)?
   
   
   
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-   -
- Jason Pyeron  PD Inc. http://www.pdinc.us -
- Principal Consultant  10 West 24th Street #100-
- +1 (443) 269-1555 x333Baltimore, Maryland 21218   -
-   -
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
   
This message is for the designated recipient only and may contain
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have received it in error, purge the message from your system and
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Re: [CentOS] 12V computing?

2008-04-11 Thread jim

12VDC is appropriate for places that don't have 
other electrical supplies. these places include 
automobiles and boats as well as remote regions 
that use windmills, creekmills, solar panels, 
car batteries, and deep discharge gel batteries, 
possibly in a mix. typically there's noise and 
variant voltage levels above the nominal 12VDC; 
any system should be designed to work with spikes, 
noise, and higher voltages--most are as a matter 
of course. 



On Fri, 2008-04-11 at 19:06 -0400, Gordon McLellan wrote:
 If you want to minimize power costs, look to higher voltage, not
 lower.   Run your computers off 208-240 volts instead of 100-120.  If
 your supply is not auto ranging, make sure it's set to the high / 230
 setting.
 
 Having a massive 12v power supply to run several computers isn't going
 to save any power.  Your second picture just demonstrates they have
 integrated the electronic power supply into the board, thus when your
 power supply fails, you can replace the entire system instead of just
 a component. It is doubtable than a 12VDC to ATX converter is any more
 efficient than an AC-line to ATX converter.  Plus the cabling to
 transfer 12V at 10a+ more than a few feet is going to be massively
 expensive - look up the I2R losses on google.
 
 In regards to cpu support, the via website mentions the C7 compares
 directly with the Pentium IV, which would make it a 686 class cpu.
 Additionally, they claim support for these extended instruction sets:
 MMX, SSE, SSE2  SSE3
 
 One thing you might want to consider, is DIY blade computing.  With
 some clever wiring, you can splice the ATX connector harnesses from
 several dead power supplies onto a modern high wattage psu, providing
 power for 4 to 6 low-end system boards arranged in a stack.  A new 80
 PLUS rated 500-600w psu should have no problems.  Pick one from the
 stack to be the 'master', and toss a hard drive on it, the rest can
 net boot from it.
 
 Gordon
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Re: [CentOS] 12V computing?

2008-04-11 Thread John R Pierce

jim wrote:
12VDC is appropriate for places that don't have 
other electrical supplies. these places include 
automobiles and boats as well as remote regions 
that use windmills, creekmills, solar panels, 
car batteries, and deep discharge gel batteries, 
possibly in a mix. typically there's noise and 
variant voltage levels above the nominal 12VDC; 
any system should be designed to work with spikes, 
noise, and higher voltages--most are as a matter 
of course. 
  


and, of course, you need 10 times the amperage at 12V... For instance, a 
250 watt system that would draw about 2 amps at 120V will be drawing 20 
amps at 12V.   this means that you need much heavier gauge power wiring, 
especially for long runs.

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Re: [CentOS] 12V computing?

2008-04-11 Thread jim

   a 100 Watt system draws a little less than 1 Amp 
at 120 VAC and about 8 Amps at 12VDC. there's about 
10 times power loss per foot of conductor and per 
connection (estimate 1/2 Ohm per connection). Yes, 
heavier guage wire is required for a lower voltage 
supplying the same power. 
   for that reason, systems using 12VDC must require 
very little power. Via's latest motherboards include 
some that draw 20 or 30 Watts and yet have pretty 
good processing capabilities. SATA solid state drives 
and USB pendrives draw very little power. there are 
systems advertised drawing less than 10 Watts (e.g. 
gumstix). the XO laptop (OLPC) is a good example of a 
fairly powerful computer that requires very little 
Wattage. 
   efficient software design--good algorithms and 
small memory footprint--improve benchmark performance 
at the feature level. software that must comply with 
legacy requirements is at a disadvantage in such 
systems. and such systems look to be increasingly 
needed, given the increasing green requirements world 
wide, not to mention the spotty power availability of 
many of the world's remote regions. 
   i believe manufacturers will be delivering systems 
that require less and less power in the near future, 
and more and more of them will be battery powered, 
not only at 12VDC but with AA and C cell batteries 
(e.g. cellphones and PIM devices). 
   as 12VDC is ubiquitous, we should see more and more 
systems designed to work off a cigarette lighter. 
they exist today. 




On Fri, 2008-04-11 at 21:28 -0700, John R Pierce wrote:
 jim wrote:
  12VDC is appropriate for places that don't have 
  other electrical supplies. these places include 
  automobiles and boats as well as remote regions 
  that use windmills, creekmills, solar panels, 
  car batteries, and deep discharge gel batteries, 
  possibly in a mix. typically there's noise and 
  variant voltage levels above the nominal 12VDC; 
  any system should be designed to work with spikes, 
  noise, and higher voltages--most are as a matter 
  of course. 

 
 and, of course, you need 10 times the amperage at 12V... For instance, a 
 250 watt system that would draw about 2 amps at 120V will be drawing 20 
 amps at 12V.   this means that you need much heavier gauge power wiring, 
 especially for long runs.
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[CentOS] 12V computing?

2008-04-10 Thread Jason Pyeron
Does anyone on the list have recommendations on 12VDC based hardware which
runs a stock Centos 4 (or even 5)?



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- Principal Consultant  10 West 24th Street #100-
- +1 (443) 269-1555 x333Baltimore, Maryland 21218   -
-   -
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 
This message is for the designated recipient only and may contain
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have received it in error, purge the message from your system and
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