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From: lance@helios (Lance Bresee)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Power Supply Calculation:
Message-ID: <7993@saturn.ucsc.edu>
Date: 22 Jul 89 22:25:07 GMT
References: <6566@cs.Buffalo.EDU> <7988@saturn.ucsc.edu>
Sender: usenet@saturn.ucsc.edu
Reply-To: lance@helios.ucsc.edu (Lance Bresee)
Organization: University of California, Santa Cruz;  UCO/Lick Observatory
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in reply to the previous reply....
worst case hard drive useage is probably around a half amp..
floppy's draw more typically, but arent on all the time..
motherboards draw very little...dram is also variable...
the number of cards you have also effects power drain..
most designers use a power supply which will handle more than
the power required by a system which is loaded to the max..
I have yet to hear of a 200w power supply being insufficient for
any AT configuration..
You are probably safe to assume that an AT with two floppies,two HD's,
and eight slots full of cards will use aroung 80 percent of 200w,
or 160w...if you have one hd and five or so cards with two meg dram
you are probably drawing 100 w... get a clip-on ammeter and isolate
one of the wires in your power cord, then turn on the machine..
that is the only way to be accurate..
Monitors are also variable and probably draw more current than the
rest of the setup...you can conserve a LOT of power if you leave
the computer running but turn off the monitor when it is not in
use...
lance