[SPARCbook] Q: Heat build-up in SPARCbook3 GX "left on 24x7"

[Steve Conley]

I got a fan from 3dcool.com which fits in the PCMCIA slot. Works
perfectly!  I used to keep my sparcbook on 24/7, but then I realised
I wasn't using it as much (since I got my SPARC 20 dual processor
up and running again) so I shut it down.


Steve

Gary Goddard wrote:
> 
> In my local electronic store (Maplin in the UK www.maplin.co.uk ) I saw a
> PCMCIA cooling fan (Catalogue code TK51F ).
> The packaging stated compatible with windows, but it looked like it just
> took its power from the port.
> Has anyone tryed one with a sparcbook?
> 
> Gary.
> 
> ----- Original Message -----
> From: "Ian Spray" <iws at tadpole.co.uk>
> To: <sparcbook at sunhelp.org>
> Sent: Tuesday, October 24, 2000 10:10 AM
> Subject: RE: [SPARCbook] Q: Heat build-up in SPARCbook3 GX "left on 24x7"
> 
> >
> > On 23-Oct-00 Ken Hansen wrote:
> > >
> > > The laptop sits on a hardwood table, with the rear portion "propped up"
> > > on those clever little "legs." I am starting to assemble my "lab," and
> as
> > > such will be moving the machine to some wire shelving in my basement (a
> > > relatively cool environment - I am thinking of placing a small 12 V. fan
> > > or two (from an AT&T UnixPC) under the SPARCbook to improve air-flow,
> has
> > > anyone else done such a thing?
> > >
> > You might also like to try a small fan blowing into the PCMCIA sockets -
> > that will try to get air moving around the CPU itself.  Blowing under the
> > machine is a good alternative, as the CPU heatsink is thermally bonded to
> > the middle of the bottom of the case.  Placing the unit on a wire mesh
> rack
> > might also help (dunno the make, but similar to the stuff on ER), as the
> > large gaps let air move, and keeping the base in contact with the metal
> > allows the shelf to become a larger heatsink.
> >
> > > Also, the laptop has remained open for he last two or three months, and
> > > while the display turns off after a period of time (great!), I know I
> > > can't close the case, as the keyboard seems to "vent" heat from the
> > > system - what are folks doing about this? Do they just leave them open?
> > > Didn't someone set some of these up as kiosks? How are you handling heat
> > > dissipation?
> > >
> > There is indeed heat vented from the top of the case.  I would imagine
> that
> > the kiosk problem is solved by not running SETI at home/dnetc or any other
> > process which keeps the CPU 100% active.  I have used a plain S3 (50MHz
> > CPU) as a firewall/NAT/router at home, and this summer it was running 24x7
> > in an ambient of up to 33C, with the temperature inside the PCMCIA socket
> > reaching 44.1C at the worst point.  This was allowing the kernel to clock
> > stop to keep the core temperature down, and it was also on a much slower
> > machine so the heat generated was much lower too.
> >
> > I did have two unexplained crashes, but the rest of the time it just
> worked
> > - there were no external fans but I did leave the screen up to help move
> > the heat.  I would not recommend running a machine like this, especially
> > not with a PCMCIA modem card in it - pulling that out really was like
> > holding a hot potato.  I did make sure that the hard drive was spun down
> > after a fairly short time, but that was only because a firewall doesn't
> > need much disc access.
> >
> > > One final question - by leaving my SPARCbook on 24x7, am I damaging the
> > > battery? The battery is installed, and the LCD shows battery life
> varying
> > > between 99% and 100% remaining... Is this drawing power through the
> > > battery or working independently? For long-term storage (I have a
> > > spare!), should I leave the laptop plugged in and turned off, or should
> > > I remove the battery and put it away? I am concerned an internal clock
> > > battery will give up the ghost and bring the SPARCbook down, with a
> > > broken clock battery...
> > >
> > The cycling is due to the charging being cut once the microcontroller
> > senses the end of charge signal from the battery pack.  After this, the
> > cells will start to loose energy as all rechargeable systems do, and once
> > it gets below the top threshold, the micro will turn the charging circuit
> > back on again.  You're just watching the hysteresis at the end of charge.
> >
> > I'm not convinced that the main battery has anything to do with the clock
> > backup - they're supposed to be independant and self powered.  I do have
> to
> > add that I haven't read the schematics for the SPARCbook machines, so I
> > can't be sure.  I would be very surprised if a dying clock battery were to
> > crash the machine though :)
> >
> >
> > --
> > Ian Spray          :  Software Engineer     :  Tadpole-RDI
> > iws at tadpole.co.uk  :  +44 (0) 1223 428 224  :  http://www.tadpole.com/
> >
> > _______________________________________________
> > Sparcbook mailing list  -  Sparcbook at sunhelp.org
> > http://www.sunhelp.org/mailman/listinfo/sparcbook
> >
> 
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