Alienware 17 R2 12V from mobo

Hi all, I'm wondering how can I get 12V direct from AW17 R2 mobo? My system was built from AW17 R2 mobo, no battery and no lcd, I'm using external monitor and direct dc adapter.

System specs:
Cpu: i7-4710
Gpu: gtx 980m 4gb
Ram: Corsair Vengeance 16gb ddr3
Dc adapter: Flextronics 19.2V 12.3A 240w

Some suggest that I tap 12V from battery port, but some said mobo won't charge when there's no battery detected. Some also suggest that I get the 12V from display port (not the vga/hdmi), but I'm not sure. Wish that any expert can help me out, thanks.

 

Probably @t456

 

It cannot turn on without a laptop screen connected by the way.

 

t456? You mean terminal 456? Where is it?

 

What do you mean it cannot turn on? The whole system can't turn on without screen connected to the mobo directly?

 

Yeah exactly this.

When my motherboard was replaced because a bios update bricked the machine. The technician didnt hook up the internal LCD connector correctly. The laptop refused to start. Even with an external screen connected trough the HDMI port. YOu will hear 8 beeps when it is not connected.

 

gosh, can I just plug in without the real lcd screen? I have the cable, will that work?

 

You mean the internal cable? WIthout the itnernal cable hooked up it will not boot.

 

Yeah I mean that cable with small hook or lock, only that cable, without connecting the exact lcd screen

 

I wonder how it senses the presence of the internal display. Perhaps it's a case of shorting a couple of legs on the connector? If so, a more elegant solution might be to get hold of the cable and short them there rather than on the socket itself.

 

I mean a forum user who can probably help

 

yea at least reduce the risk of spoiling the socket

 

With a screen connected. WIthout it is sitll not possible.

 

i think the other way is to short legs of the connector as mentioned by guttsy

 

Unless you short the wrong ones in which case it still won't power on, but possibly more permanently.

 

omg... hope that won't happen...lol

 

It is reading the monitor state I think.

 

maybe, let's get back to my initial question, how to get 12v from mobo??

 

The battery pins could work and can deliver between as little as ~7.5W and up to 30W, this depends on the implemented charging circuit of the laptop. And, indeed, probably requires the battery to be hooked up, defective or otherwise. This is also a bit risky ... should only consider this if the display port is not an option since the voltage it turns out is not only a fair bit too high, it is variable as well, which may not be very healthy for the device(s) you want to power.

To make it boot without an lcd you only need to leave its firmware intact; ' signal is there' -> ' lcd is present'. You could salvage/separate the pcb from a broken lcd (~$15) and hook up the cable to that. This needs only four of its 30 wires to work, the 4+4 wires originally intended for backlight power are then at your disposal for whatever you want to power. Output is limited to a little under 6W, this being quite an energy-friendly panel. Benefit is that it's exactly 12V, a steady source and that it can even be turned on/off using the Fn key used for 'display on/off', provided these pins are left alone.

Hm ... and I'm confused ... did this system boot with no internal panel connected or not? If not, then try hooking up a monitor over VGA; this should take first precedence, even before an internal panel.

 

he can conect a display with the AGA port ? using the AGA and directly conecting the display to the GPU in the box ?

 

Thanks for your support!

At this moment I cannot answer you yet because my parts are only half way to me, however I'll update you guys the progress once I started working on it.

What if I only plug in the lcd cable and short it to fake the screen presence? Cuz I have the cable only but not the screen, wish it can be done without additional cost. If plugging in vga with ext monitor will make it work would be the best. Only can make changes to firmware if it can be power up.

What if I need the 12v for additional pcie x4? Getting from lcd power port is the best?

 

Aga? You mean the graphics amplifier? I don't think I want to buy that XD

 

WOnt boot. Even an external monitor hooked up will not let the laptop boot. It needs it internal display signal for it to boot.

 

hope that shorting the cable will work

 

Will not work, it needs to find the firmware present. Fetch this $11.60 panel and use its pcb, that's just the part that dangles below the screen, so it hardly takes up any space.

Yes and yes. But again; that depend on how much power you want to draw from that, so how much watts are we talking about?

 

how much W we need for a pcie 4 lane card? sorry idk

 

it's the inverter I assume

 

perhaps this

http://www.ebay.com/itm/Dell-Alienw...783840?hash=item58d6acff60:g:o4kAAOSwp5JWU9dd

 

Specs for pcie-x4 is max 5.5A, 66W? I found on the web.

 

Yes, but for what? A usb-adapter or led-strip is something else entirely than a gpu, so ... again; what component do you plan to run at 12V? If it's a gpu you're thinking of, then forget it; get a dedicated adapter rated for the watts your gpu requires.

Well ... you could tap into a working battery, which can deliver ~200W, but that may kill or at least diminish the lifespan of the gpu, considering this 4-cells-in-series model will output as much as 16.8V when fully charged. Hacking it into a 3-cell may work, as that'd limit it to ~12.6V, yet that requires opening the pack and some soldering.

 

Definitely not gpu, the built in 980m is more than enough. Maybe to run cooling fan? Or SSD??