[time-nuts] Modern motherboard with RS232 port

jmfranke jmfranke at cox.net
Sun Aug 19 15:36:36 EDT 2012


There is no difference for a resistive load. For a reactive load, you have 
to take in account the phase angle between the current and the voltage. If I 
remember correctly, power = Volts X Amps X cosine of the phase angle. Some 
refer to the phase angle as the power factor.

John  WA4WDL

--------------------------------------------------
From: "Tom Knox" <actast at hotmail.com>
Sent: Sunday, August 19, 2012 3:19 PM
To: "Time-Nuts" <time-nuts at febo.com>
Subject: Re: [time-nuts] Modern motherboard with RS232 port

>
> Hi Ed;
> I may not have had enough coffee yet, but if Volt X Amps = Watts why would 
> there be a difference?
> Best Wishes;
> Thomas Knox
>
>
>
>> Date: Sun, 19 Aug 2012 12:35:51 -0600
>> From: ed_palmer at sasktel.net
>> To: time-nuts at febo.com
>> Subject: Re: [time-nuts] Modern motherboard with RS232 port
>>
>> It's important to remember that on a computer, the wattage shown has no
>> relationship to the wattage pulled from the socket.  The numbers shown
>> are maximum values.  You have to measure the power draw and you have to
>> measure it in volt-amps, not watts because that's how residential power
>> is measured (at least in North America).  Buy an energy meter that shows
>> volt-amps.  They're relatively cheap - typically less than $50.
>>
>> Ed
>>
>> On 8/19/2012 11:06 AM, Chris Albertson wrote:
>> > This sounds like a newer version of the board I use.   The thing to 
>> > check
>> > is if the CPU heat sink has a fan or not.  Having no fan indicates that 
>> > the
>> > CPU is not using much power.  It also removes a common failure point.
>> >
>> > To reduce power even more.  On an NTP server you can unplug the 
>> > keyboard,
>> > mouse and monitor and if you have other servers on the LAN configure 
>> > one as
>> > a "boot server" and have it run TFTP then your NTP server does not need 
>> > a
>> > disk drive.  It can run off a "RAM disk".  This makes it very fast, 
>> > even
>> > faster than a SSD and it saves some cash.  Makes backup easy too as 
>> > there
>> > is nothing to backup if there is no local storage.  If you don't have a
>> > TFTP server use a small notebook size disk drive. Even a 80GB drive is
>> > overkill.  You can also boot from a USB thumb drive and run a RAM disk.
>> >
>> > It is worth it to look at your electric bill to find how much you pay 
>> > for
>> > power.  Here I'm at $0.21 per KWH.  A full size PC server can use 250W 
>> > or
>> > more.  There are 8760 hours in a year so you get $460 per year to run 
>> > that
>> > 250W PC.  The little Atom will pay for itself in just a few months. 
>> > The
>> > first time I did that calculation, my "power hogs" where given away.
>> >
>> >
>> >
>> >
>> > On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE <stanw1le at verizon.net> 
>> > wrote:
>> >
>> >> Hello The Net,
>> >>
>> >> For your consideration:
>> >>
>> >> The INTEL model DN2800mt ITX mother board uses a ATOM CPU and
>> >> draws about 11 watts of AC power when configured as:
>> >> (I have not measured DC power yet.)
>> >>
>> >> 30 GB OCZ Nocti mSATA solid state drive,
>> >> WIN7 pro, 64 bit, USB keyboard and mouse
>> >> APEX MI-0008 case.
>> >>
>> >> Also has:
>> >> parallel port available on mother board, you extend to a connector
>> >> RS232 serial port available on mother board, you extend to a connector
>> >> a single DC power supply from 11 to 19 V DC.
>> >> 1 each PCIe expansion port, I will use with a premium 4 channel sound 
>> >> card
>> >> SATA ports available for HDD/SDD,
>> >> USB ports are available,
>> >> Motherboard sound, and Gigalan.
>> >>
>> >> I have not played with NTP, (yet), but it sounds like a decent time 
>> >> nut
>> >> technical challenge.
>> >>
>> >> My application is for a remote site with only 13V DC power available 
>> >> from
>> >> PV/batteries.
>> >> Then use fiber ethernet to get off site.
>> >>
>> >> The INTEL website would have further details.
>> >>
>> >> Stan, W1LE    Cape Cod   FN41sr
>> >>
>> >>
>> >>
>> >>
>> >> ZZZZz
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to 
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
> 





More information about the time-nuts mailing list