Laptop as carputer, hardwiring, power issues

**boostd4** · 03-25-2005, 08:57 PM

I searched for about half an hour and read some relevant threads but still have some questions.

After searching for parts to build my own carpc (not having any spare stuff lying around).. piecing together a box is NOT inexpensive. Then I looked at the pre-built stuff like capuccino pc, car-bot, etc.. .and those are upwards of $700 (and that's just the basics).

So I got to thinking... why not just use an old laptop? It's got everything I need. I went on Ebay and searched and found several laptops that were 1ghz+, 512-2gb ram, dvd/cdrw, VGA/line out, USB, built in wifi, for $350-$500. Seems like a bargain compared to buildilng my own. I know a 7" touchscreen will run me about $280, then all I have left to do is figure out power, right?

I read a post about how I could probably find a $50 power source for my laptop on ebay - what's that mean? My newbie logic says I get an AC adapter for the laptop, plug it into a power converter, and hardwire the power inverter to battery/ground. Then run an SDC.

In order to run an SDC, I'll have to take apart the laptop and try to figure out how to hardwire into the power button right? I've never taken a laptop apart, and have limited soldering/electronics skills.

I'm dumb. I need a tutorial, or at least a basic walkthrough. The searches I've done are usually people asking questions halfway into their build. I'm trying to get a grasp of what skills I need to start from the beginning. Any help appreciated. Sorry for the NEWB bandwidth.

-Adam

**Chris31** · 03-25-2005, 09:08 PM

You need a DC-DC adaptor. This is a 12V car battery to laptop adaptor. They should cost around £30 or cheaper. Most are around 60W, get a more powerful one depending on the laptops power requirement, 70W > perhaps?

The SDC, yeah just solder the wire to the power button. Some solder them to the docking station. If your laptop support wake on ring through the comport then you can use this. Some can only wake up from standby but not from fully off.

No need for tank because the laptop already have this.

**Chris31** · 03-25-2005, 09:10 PM

Search for "fake ups" if you wanna build a simple SDC. This connect to the comport.

**Chris31** · 03-25-2005, 09:12 PM

Second hand laptop for carpc use is cool huh. Join the desktop bashing club

**boostd4** · 03-25-2005, 09:13 PM

Originally Posted by Chris31

You need a DC-DC adaptor. This is a 12V car battery to laptop adaptor. They should cost around £30 or cheaper. Most are around 60W, get a more powerful one depending on the laptops power requirement, 70W > perhaps?

The SDC, yeah just solder the wire to the power button. Some solder them to the docking station. If your laptop support wake on ring through the comport then you can use this. Some can only wake up from standby but not from fully off.

No need for tank because the laptop already have this.

What's "tank"? And not to be too much of a bother, but could you perhaps show me an Ebay listing of the DC-DC inverter I would need? How does this inverter work - does it take the place of my A/C power cord that came with the laptop? Does that mean I have to dissassemble the laptop and try and solder the DC somehow to where my A/C Power cord plugged in? I kind of like the idea of keeping the power chord usable, in case I have to take the laptop inside for some reason.

Thanks for the response.

**boostd4** · 03-25-2005, 09:17 PM

I've found that you can get a fairly NEW used laptop on ebay that has a broken LCD for almost nothing...

I searched a few minutes ago and found a P4 1.6ghz M Processor with 30gig, DVD/CD/RW 512mb (to 1gb) and all the goodies a Sony Vaio comes with for $375.... guy said it's starting to get random red lines across the display... you can still see what's going on, but will need to be replaced - said that it looks normal when plugged into an external monitor... now that's a steal for someone planning on using a Touchscreen LCD.

**boostd4** · 03-25-2005, 09:21 PM

Sorry, one more thing.. How do I determine how much power I need my DC-DC inverter to be if my laptop doesn't list the component's power draw? Would the manufacturer's website list the total power draw?

**Chris31** · 03-25-2005, 09:23 PM

An example of DC-DC adaptor you may need.

http://www.maplin.co.uk/Module.aspx?...dID=4&doy=26m3

This plug in to the cigarette ligher socket and the other end plug in directly to the laptops power socket. You DONT NEED the AC adaptor anymore.

Tank - A spare battery so the pc can carry on operating as normal when the engine is started. A reboot or freezing normally happen to the PC during crank. The spare battery kicks in temporarily during the crank. Some PSU doesnt need a tank this is because its able to provide a good supply even though the car battery had dip down as low as 8V during crank.

SEARCH SEARCH SEARCH, you find more detailed infos

**Chris31** · 03-25-2005, 09:27 PM

Check the original AC adaptor that came with your laptop, that should tell you the power output in WATTS and its output VOLTAGE.

Then just check if the DC-DC adaptor meets this requirement. In most cases it does unless you got some mega power laptop.

Read the FAQ on the link I just sent you, some poeple have asked some similiar qs to yours.

**boostd4** · 03-25-2005, 09:53 PM

Originally Posted by Chris31

Read the FAQ on the link I just sent you, some poeple have asked some similiar qs to yours.

That adapter looks just like the car-adapter I can buy from Sony for the Sony laptop, is this the same thing?

Also, I don't want to have it plugged into my cigarrette lighter all the time. If I cut the cig adapter off the end, should there be a power and ground wire in the insulation so I can hardwire it to the fusebox?