Headless PB g4 1.67

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Headless PB g4 1.67

I am going to attempt to remove my display on my powerbook, and was wondering if this unit will function normally with just a monitor hooked up to the DVI plug? i know the machine goes to sleep if its on battery with the lid closed, but what if there is no lid? Smile i just wanna know what to expect if someone else here has done such a thing or knows where to find more info. thanks!

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should work fine

The "sleep when closed" function works with a magnet (in the lid) and a reed switch (in the body). Without the magnet coming in proximity to the reed switch, the machine will not know the lid is closed. This is true even when the lid *is* closed and the magnet is missing, or the reed switch is missing or nonfunctional.

I suppose if you *needed* the machine to sleep, you could fool the reed switch by placing a magnet over it. A little trial and error should help you find where the reed switch is located. Should be along the edges, and not too close to the hard drive.

The machine will work *mostly* normally using only the DVI and no built in screen. You'll need to turn on mirroring and adjust the resolution settings to make it send the primary monitor to DVI.

Until your resident OS is booted, the machine will look for the built-in first, even presume that it is there even if it's not. What this means is that you won't be able to boot to another disk like a Mac OS installer or Disk Warrior, because you won't be able to see the primary screen. The monitor attached to the DVI will default to a secondary screen, and you won't be able to turn on mirroring.

You should still be able to install Mac OS or run diagnostics like Disk Warrior by booting the PowerBook into target disk mode and attaching it to another Mac via Firewire.

Final caveat: the Airport and Bluetooth antennas are located in the screen assembly. You will not have good (read: any) AP or BT reception in this machine. You'll need to use the built-in keyboard and trackpad, or USB keyboard and mouse. You'll also need to connect to your network with an Ethernet cable.

This is the behavior I've seen in my headless MacBook "Ichabod." I presume that the PowerBook will behave the same way. YMMV: please keep us posted.

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thank you for all your input!

thank you for all your input! i am planning to keep the broken screen it has now around just for rough times where it needs to be hooked up for installing OS's and what not, 2/3 of the screen is still viewable haha. one of these days when i work up the nerve to go through all the steps i saw on ifixit's website, i will see how this all works! with that said, if i left the cable coming out of the laptop and unplugged it on the screen side of things (if possible) would that (electrically) be kosher for the powerbook?

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I believe if you put the mach

I believe if you put the machine to sleep and then attach external keyboard, mouse, and monitor, you can then wake it as though its a desktop (with the built in screen still closed). I know my powerbook g4 12" worked this way, but my newer macbook does not.

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Re: should work fine

I suppose if you *needed* the machine to sleep, you could fool the reed switch by placing a magnet over it. A little trial and error should help you find where the reed switch is located. Should be along the edges, and not too close to the hard drive.

Actually, on at least the 1.5Ghz models the reed switch is under the trackpad, pretty much right over the top of the hard drive. Not sure where it is on a 1.67g Ghz but I'd bet it's in the same ball park.

I've fooled around with "headless" mode a bit by setting a small refrigerator magnet on top of the reed switch, and in doing so I discovered that if you have a keyboard and mouse attached you can turn on the system with the power switch and have it come up with the primary display on the DVI port. (I was investigating whether it would be feasible to run jumper wires from the back of the power switch to an external pushbutton and essentially tape a pretty badly mangled Powerbook permanently shut for desktop use.)

If you decide to go with the "magnet on the trackpad" idea don't use one of those super-powerful rare earth models, obviously. It needs to be *slightly* more powerful than that "magnetic rubber" that comes on the back of pizza place business cards and whatnot, but not by much.

EDIT: As for whether it would be kosher to run the machine with the LCD display cable unplugged, I'm honestly not sure. I know you can damage the video circuitry if the cable is cut or otherwise damaged in such a way that it causes a short, but just hanging unplugged and unshorted... someone else could probably comment.

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Re: thank you for all your input!

...if i left the cable coming out of the laptop and unplugged it on the screen side of things (if possible) would that (electrically) be kosher for the powerbook?

It's going to be an *awful* lot of work to open up the display assembly and disconnect all the cables in a 1.67 PBG4. In the days when this model was under warranty, Apple didn't send just the panel or the cables: they sent the whole assembly. If Apple doesn't see fit to hassle with it, why should you?

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again, very good info to know

again, very good info to know, i might just try the magnet on the switch trick with something better than a Fridge magnet Smile but what i dont want is a screen left on the machine to either block the speakers or over heat it, or be left up in front of my 20 inch lcd thats hooked up to it Beee i wonder if i can just break the hinges off and set the LCD on top of this one? haha ok so maybe thats a bit wrong.. i really should just buy a new display for it but i really dont wanna spend the money, it still needs a battery to be portable so why bother..

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Overheating...

I haven't had a problem with Aluminum G4s overheating with the lid shut. I ran mangy G4 I was pondering the power switch hack on closed and hooked up to an HDTV for several weeks without a problem. If you're really worried about heat dissipation a more effective strategy than leaving the lid open (or tearing it off) is to close the lid and prop the machine in a vertical position (hinge down works well, since there aren't any ports to obstruct and you can still access the CD-ROM drive) as exposing the bottom provides plenty of radiating surface. As for blocking the speakers, well... they're nothing to write home about anyway, why not just plug in a set of external speakers? They'll be better anyway.

Honestly the biggest annoyance with using a Powerbook that way is that Apple only saw fit to put two USB ports on them, so you pretty much have to use a keyboard with a built-in hub port for the mouse. (IE, one of Apple's keyboards? It may just be me, but I've had bad luck with using keyboards on the other side of third-party hubs with clamshell mode.)

It would certainly be "nice" if Powerbooks had options (like *any* cheap PC laptop does) that would easily allow disabling the internal screen whether you had the lid open or not. But Steve Jobs doesn't use his computer that way, so why would you want to?

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i understand the speakers are

i understand the speakers arent that great, but i was also planning on not using external keyboard or mouse Smile it'd be awesome to just plug in power and monitor and let it fly

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initial use is somewhat disap

initial use is somewhat disappointing. i cant seem to find the magnetic switch that shuts off the internal display, so im stuck using resolutions that the internal is capable of displaying.

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Magnetic switch...

If I get a few minutes sometime I'll try to figure out where it is on mine... I actually have a G4 1.67 lying around that I haven't turned on for a year and a half.

Alternatively, you could try feeling around the screen for it. It's literally a tiny little magnet just taped to the screen, so you can dowse for it with an iron/steel wire and extrapolate from that where the spot would be with the lid closed.

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I think...

I think the magnet switch may be in the frame near the F7 / F8 keys. I ran a small magnet around the perimeter of my 13.. GHz 17" G4 PowerBook, and when i got to that area, my display shut off, so...

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thank you both for the ideas!

thank you both for the ideas! as far as the screen goes, its gone lol.

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Okay, how to do it.

thank you both for the ideas! as far as the screen goes, its gone lol.

There, I've uploaded some images to this site showing how to make it go into "external port only" mode. (I apologize for the low quality cell phone-y nature of them.) I just happened to have a beater Powerbook with a peeled screen lying around, so all the better. To reiterate from the descriptions I attached:

IMAGE(http://www.applefritter.com/images/imag0014-24820_640x480.jpg)

On the 1.5 Ghz Powerbook the magnet is taped to the back of the screen at a location which is approximately six inches from the left side and about 2.75 inches from the front lip of the machine when it's closed. The measurements are a little sloppy because A: I'm lazy, and B: this machine is pretty banged up and the screen frame isn't quite on straight.

IMAGE(http://www.applefritter.com/images/imag0018-24821_640x480.jpg)

I lied. At least some of those little vinyl magnets are powerful enough to activate the sleep sensor. (I've penciled a little cross on the trackpad approximately where it is. "Now it's Marge's Time to Shine!")

IMAGE(http://www.applefritter.com/images/imag0016-24822_640x480.jpg)

Stick the magnet on the sensor, the laptop falls asleep. If you have it in the right place when you hit a key to wake it up it will disable the LCD and just run with the video output port. The picture's too low-res to see, but I can set resolutions up to the 1920x1080 maximum the monitor supports.

Once you *have* the machine in this mode it appears you can pick the magnet up and it will continue working until it falls asleep again or reboots.

If your machine is the "low res" 1.67Ghz model I'm positive the sleep sensor will be in the same place. It's *possible* it might of moved if you have the "high-res" DDR2 equipped machine. (I sort of doubt they would of, but I've never been inside one.)

EDIT: Forgot to mention... if you power on the machine with the magnet there it will go straight to external display mode, never enabling the LCD at all. That implies that to make a permanently headless Powerbook you could either:

A: permanently glue a small magnet to the top of the trackpad. That will make it somewhat annoying to use, but you could always use a USB mouse.

B: You could open the machine up and put a bit of magnetic material directly on the switch itself, or possibly just damage it so it's always closed or open. (Whichever shuts the display off.)

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i love the pics and the info!

i love the pics and the info! i just need to find a strong enough magnet to try this out, because id really love to use the 1920x1080 on my 32" TV! haha

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Re: i love the pics and the info!

i just need to find a strong enough magnet to try this out, because id really love to use the 1920x1080 on my 32" TV! haha

Just remember, you don't need much in the way of a magnet. This vinyl magnet I used is just *slightly* stronger than average for this stuff... it might hold a sheet of paper to the 'fridge in addition to itself. Don't go waving one of those finger-smashing neodymium magnets around near the hard disk.

(The magnet on the back of the display is undoubtedly more powerful than the magnetic vinyl, but it has to affect the switch from about a quarter inch away, from behind the LCD.)

If you don't get any response from setting a small magnet on the trackpad where I've X-ed out it could be the sensor is somewhere else on your model. In that case, I'd say you could take a somewhat more powerful magnet (a magnetized screwdriver, perhaps) and just wave it slowly over the top of the system. The switch is there *somewhere*. The only catch you could encounter is if it's the middle of the keyboard or somewhere else similarly inconvenient. But I bet on it being in the trackpad. The "iFixIt.com" disassembly guides don't mention there being a separate reed-switch sensor boards for any of the 15" AL models. (Some other models, like iBooks, did have them.)

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yea i dont feel like corrupti

yea i dont feel like corrupting the hard drive.. Blum 3

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What's its name?

So will you be calling this machine Marge, then?

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Re: Headless PB g4 1.67

little update on the headless wonder, turns out it can boot into the tiger installer dvd if you leave the magnet on the trackpad long enough. however, the one i used was so strong(only one i could find) it killed and i mean KILLED the hard drive. live and learn....

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Re: Headless PB g4 1.67

Another thing i learned is a way to get the installer to show on an external display without the use of a magnet. simply boot the machine from the cdrom/dvd and wait till its completely booted up before attaching the monitor, as soon as it sees it, it will force mirroring on its own. pretty nifty, if i only knew that BEFORE i killed an 80gb hard drive..

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Re: Headless PB g4 1.67

I am going to attempt to remove my display on my powerbook, and was wondering if this unit will function normally with just a monitor hooked up to the DVI plug? i know the machine goes to sleep if its on battery with the lid closed, but what if there is no lid? Smile i just wanna know what to expect if someone else here has done such a thing or knows where to find more info. thanks!

LCD are easily interchangeable between aluminium PowerBooks, hope this can help:

http://www.webalice.it/beniamino.cenci.goga/DIY/PBG4_sleep_magnet.html

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Re: Headless PB g4 1.67

since ive finally gotten around to tearing the machine down to swap hard drives, i know i could change the LCD on it, but it also needs pram battery and main battery. its a money hog for just playing around with old stuff. its a little too slow to use on the web it seems. great link though, thanks!

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Re: Headless PB g4 1.67

As you can see from my signature, I have also faster Macs, so I can say that the PB G4 1.67 is still a viable computer, I can hardly notice speed differences between it and the MacBook white,

Ben

PS Thanks for your intest on my DIY on going page project

Ben

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