Easy power button mod

[Miskatonic]

Just did this mod on my old netbook which I'm using inside my bartop build. I just came up with it myself, didn't follow any plans, and it was very simple.

The keyboard was already removed from the laptop due to a "constant keypress" issue and underneath it was the ribbon connector connecting the on/off button to the mainboard.

Your pc/laptop may be different to this. All you need to do is to trace the line from the power button to where it meets the mainboard, then you know you're messing with the right thing.

Under your powerbutton will be a temporary switch, usually a very small plastic square with a round button on top that's pushed down by the larger button above on the chassis when you depress it. However, in my case it was like a really tiny gold penny sort of shape about 3mm across. either way, this will be connected to the power part of the board with 2-4 legs. To test which legs you need to solder to, simply get the wires you intend to solder connected to a button and a microswitch and touch them against 2 terminals (legs) whilst pressing the button repeatedly, if they don't do anything then try another combination of terminals (always using each wire on a different leg). When the computer jumps into life, those are the legs to solder to. You will have to be careful when soldering so as not to bridge any other connections but if you have any experience at all in soldering you should be fine.

Many people would use a multimeter to determine which of the legs is carrying the signal but I can't find mine so this "probing" method worked fine and, to be honest, a lot of people don't have a multimeter so this is much simpler for them.

sorry for the bad pictures I just took them with my phone but they should give "the general idea". You can see my solder work is quite shoddy, just did it all handheld without clamps and with, unfortunately, the most clublike soldering iron I have (I still haven't unpacked a lot of stuff from moving house, yet*)

*and it seems really important to build yet another bartop before actually having a totally "sorted" living space. Lol.

[Miskatonic]

NB: for pc "towers" and standard desktops the power button assembly is usually a lot simpler to hack as the wires come away from the button itself and you can just hack into these and solder in instead of needing to solder to the tiny legs around the clicker itself. Much easier. Don't over complicate things if you can avoid it :-)

[Miskatonic]

just did the same with my monitor power button, too, so all controls for internals are now controlled by external buttons so I can close off the back for the time being :-)

[dmckean]

Is there any easy wait to connect this stuff to a relay so everything can turn on when you plug it in?

[Miskatonic]

Not sure about a relay but you could technically connect more than 1 device to one button. I could have, for example, the pc and the monitor on the same button for example. I suppose for most people that's all that's in their cabinets. If you have a light for the marquee that could be connected to the same button, too. I just like having them separate as sometimes I might want to turn the screen off but not the computer, like on my "blind days" when I pretend to be blind but still fancy the occasional game of arkanoid or suchlike.

[dmckean]

Yeah, I'm not sure either. I should probably search the carputer forums and see what they use to automatically turn on their computers on ignition.

[Miskatonic]

I would imagine it'll be as I suggested above with the computer connected to whatever fires/turns on the car so it receives the signal at the same time. My "everything on one button" method is probably the same idea, tbh, and would definitely work.

[dmckean]

It looks like it's more complicated than that. They use microprocessor controlled power sequencers that control a range of functions and are built into the DC-DC power supplies used for the powering the PC in the car. They also make a few stand alone ones like this:

http://www.mpegbox.net/shutdown/index.html

[SavannahLion]

Depending on your desires you have a range of options.

Old school method was to use a capacitor in lieu of the switch then use a power strip to manage turning everything on. Modern PC's (and some monitors) will have a setting buried somewhere that allows "Wake on Power Loss" or some such. Both similar configurations have been discussed in numerous threads.

A newish design eschews hacking the power switch and, instead, uses a "computer controlled power strip" (hint: check Amazon). I forget the favorite model but there are variations on the same concept. They all have one "live" socket and the rest are computer controlled. The desired model tends to have a microcontroller that determines when the PC is powered on then activates the other sockets. In a round about way, one switch   Another version I've seen has the power strip as a USB device. When the PC is powered up, it sends a command via USB to "wake" any other sockets as desired. Pretty cool, but I don't really like having driver dependent device if I don't need it.

Be very careful hacking the power switches of each device then tying one switch to all the devices at the same time. Unless the switch is ganged, you might run into an oddball device that wants to wake up when everything else wants to "sleep". Or worse, some knuckle head engineer is still sending high voltage through that switch. Relays will help with this. I prefer not to use relays unless I have to though.

The automotive harnesses and power controllers are very good but, IMHO, a bit pricey to last I checked into it. The uSDC20D is $40 by itself! The power strips are pricey too but they work straight off of 120v with virtually any PC and can attach up more than a few accessories such as monitor, Marquee light, and audio amplifier.

[SavannahLion]

It looks like it's more complicated than that. They use microprocessor controlled power sequencers that control a range of functions and are built into the DC-DC power supplies used for the powering the PC in the car. They also make a few stand alone ones like this:

http://www.mpegbox.net/shutdown/index.html

That particular model has been discontinued. :/

It's been replaced with a different model. Same concept, far more features.

[rust2dust]

I took apart a suzo happ button....as I wanted to power on my cab with the same buttons I used for the cab if you take the top tab out it just gives it the power to turn on......but it will not turn off until you hit the button again. So I wired it to the pc power...
Simple fix.

[Miskatonic]

I took apart a suzo happ button....as I wanted to power on my cab with the same buttons I used for the cab if you take the top tab out it just gives it the power to turn on......but it will not turn off until you hit the button again. So I wired it to the pc power...
Simple fix.

being as a pc on/off switch is momentary anyway I don't see why you need to bother taking tabs out. I'm using a standard button (same as controls) and, as it's momentary, it works fine for switching on and off the pc and monitor, no dismantling required. I'm intrigued as to what difference this would make ?

[Malenko]

I just came up with it myself, didn't follow any plans, and it was very simple.

Not to sound like a dick or anything, but tapping the two leads and wiring it to an arcade button is like the very first step to making your own arcade controls. You don't need to take tabs out or anything, one to ground and one to NC. Welcome to the very basics.

[dkersten]

Personally I wouldn't use an arcade button.. too easy to push by accident even if it is mounted in a discrete location.  "vandal" type switches work better as you have to make a little more effort to push them.  I wouldn't chain any power functions together either as sometimes power buttons have multiple functions and some devices might have a different state after power is removed and restored.  So your monitor might turn on if power is cut when it is on, but the laptop wouldn't, so if they are chained, you might get them backwards and have a tough time switching it back.  Also, holding power for 5 seconds performs a "hard" reset on the laptop, but that wouldn't work for a monitor. 

[pbj]

C'mon, now.  Whatever happened to jamming a toothpick into the monitor power switch?  And shoving a $2 relay into a $2 power strip and driving the outlets with your PC's USB port?  You guys have grown complacent. 

[RxBrad]

I just bought a bunch of jumper wires from Amazon that could plug directly into the jumpers on my PC case / motherboard.  This way, I don't have to cut any of the case wires, and both the switch on the case and the arcade button will work as a power button.

I used a fancy LED button from GGG.

I wired up the switch to the case & motherboard PWR SW leads...

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Splicing a button between PWR SW motherboard headers and corresponding case wires:

Mobo ---+--- Case Wire
        |
       COM Lead on button

       NO Lead on button
        |
Mobo ---+--- Case Wire

Then did the same thing, connecting the button's LED leads to the Power LED Mobo leads & corresponding case wires

(OK.. before anyone asks for photos..  I haven't actually done this yet.  It's just what I plan on doing.     )

I have all of my components plugged into a smart power strip.  So, when the PC powers on, it supplies power to everything else in the cab.