Xref: utzoo comp.sys.ibm.pc.hardware:9345 comp.sys.amiga.hardware:9785 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!uakari.primate.wisc.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!jdickson From: jdickson@jato.jpl.nasa.gov (Jeff Dickson) Newsgroups: comp.sys.ibm.pc.hardware,comp.sys.amiga.hardware Subject: Re: TURN COMPUTER OFF OR LEAVE ON? Message-ID: <1991Jun3.212159.27391@jato.jpl.nasa.gov> Date: 3 Jun 91 21:21:59 GMT References: <1991May24.033650.15836@cbnewsc.att.com> <20114@rsiatl.Dixie.Com> <1991May25.151636.679@monu0.cc.monash.edu.au> <1991Jun3.194555.3525@newserve.cc.binghamton.edu> Reply-To: jdickson@jato.Jpl.Nasa.Gov (Jeff Dickson) Organization: Jet Propulsion Laboratory, Pasadena, CA Lines: 28 In article <1991Jun3.194555.3525@newserve.cc.binghamton.edu> consp03@bingsuns.cc.binghamton.edu (Kriston J. Rehberg) writes: >At our school, we have SUN workstations that are left on 24 hours a day, >but we turn off the monitors for the simple reason that they consume too >much power, burn the login prompt into the screen, and create excessive >heat. You should always turn the monitor off when you leave for any >length of time. On the other hand, the computer doesn't have components >that rely on a constant heat source to operate properly (monitors do, >unfortunately) and thus shouldn't pose a threat. Interestingly, Apple >doesn't let you turn the monitor off on any of their B/W models. > >Best, > >Kris > I've heard that it is less expensive to run flourescent lighting 24 hrs/day. This is because more current is used to "juice" the ballast when its first powered, than is used during its operation. Many office buildings do not reguarly cycle their flourescent lighting for this purpose. I would imagine that a CRT is similiar. A CRT tube basically behaves as a large capacitor. This means that when power is first applied, an abnormal current surge is required to "charge" it up. I have a SUN display terminal here at work. It's left on all the time. It, however, has a screen saver type thing that blackens the screen and displays a varying pattern of blocks. This saves the phosper from being "burned" and also cuts down on the amount of heat it produces. Perhaps someone with more insight could elaborate on this further. -jeff