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Laptop ps replacement

Last response: in Components
July 10, 2012 10:32:36 PM

I have a laptop that requires a 19v dc 55w power supply. I have a 24v dc 70w ps that fits the jack. Big question here is - can I safely connect such a supply without damage? I know most motherboards power divider sections are built for some under/over tolerance but we're talking about 5v over rated. Anyone know a general tolerance for variation? This is a total curiosity, the equipment is outdated anyway and the manf nolonger exists. Plus I couldn't find a generic. So, thoughts please? Thanks.

More about : laptop replacement

Best solution

a b ) Power supply
a c 249 D Laptop
July 10, 2012 11:32:30 PM

Hi :) 

I own a lappy repair company.....

The answer is NO !!!!!!!!!!!!!!!!!!!!!!!!

It WILL DAMAGE THE CHARGING SYSTEM AND MOTHERBOARD.....assuming you dont have a fire first....:( 

If you try it have a FIRE EXTINGUISHER handy and do NOT leave it plugged in and go to bed etc :( 

And the general tolerance as you put it is around 1 volt....and even then i have seen chargers blow motherboards with only a 0.5 volt variation.... and its the VOLTS you have to worry about ...not the watts...

All the best Brett :) 
July 18, 2012 3:51:01 PM

Thanks Brett! Since it was a bit outdated and mostly going to be experimental I decided my first experiment would be this one. I pulled the battery out, plugged it up and all seemed ok for the first ten minutes. Then I started noticing that hot electronic smell slowly coming on. I powered it off immediately and pulled the plug. Waited a half hour then tried it again just to make sure I hadn't fried it and it came on so I powered it off immediately again.

I then setup a multimeter in dc voltage mode to measure potential just before the jack with some spare parts. I frankensteined a high watt volume pot from an old stereo. Connected it in series with the (+) line and started at zero. Hooked the power jack into the laptop and started from zero. I adjusted it until I hit right about 19.3v and then turned on the lappy. I let it run for 2 hours and never got the hot smell again. The pot does get kinda warm while using it now and I can only assume this will eventually fail but for now it works!

Just thought I'd share the results of my first experiment on my experimental laptop. It's a Toshiba Satellite, can't find the model number as the stickers on bottom are toast. It is from around 2004 or so.
July 21, 2012 1:26:25 AM

Best answer selected by auriuman78m.