You need a 12volt Charger/Power Adapter that is compatable with your Laptops input voltage (e.g. 19v). Some have adjustable voltage settings.And you need a packet of 'convertable DC output plugs' to suit your laptop. Some charger/adapters come with them.
Similar to wots here..... www.computeronline.com.au/products.php?C_ID=26&S_ID=421&PROD=24845 But shop around by all means as this is just an example of what you will need.
I've been using one for years to run my laptop from the ships batterys so as to be able to run my charting system, be connected to the internet via a USB modem connected to my tricky antenna and watch TV through a USB Digital TV Tuner. Too easy.
Select to expand quoteHG02 said..
Just wondered what every one uses to power there lap tops on board?
Check what voltage your laptop requires first. I used an older Toshiba first that had a voltage of 15volts and with the battery removed ran straight off the ships 12v supply. Now I use a newer Toshiba that runs of 19 volts and have the battery removed and run a normal convertor. Note that if you remove the battery in a permanent installation the current draw is quite a bit lower. Check out my photos.
Select to expand quoteHG02 said..
Just wondered what every one uses to power there lap tops on board?
Lexmark asked me yesterday so I thought Id ask the question on the forum thank you for your imput 
