Using a Power Supply instead of a charger to power a laptop

McCrisis

Honorable
Jan 26, 2014
1
0
10,510
How feasible is it to use a power supply to power a laptop?

I have an old and used laptop. An HP Elitebook 8540p. Around an year ago, the charger that I had received with it fried. Since it was an old system, I couldn't find any new or genuine chargers so I had to buy a cheap knockoff charger. The charger I bought fried after 2 months or so. It's replacement did too. And the replacement after that.

Now, the battery backup of my laptop has steadily decreased to a mere 10 minutes or so. My current laptop charger is now constantly plugged in to a wall outlet whenever I use my laptop. As a result of this constant connection, my chargers begin overheating and fry within weeks.

Since my laptop chargers are basically functioning as PSU's, I was wondering if it were possible to use a PC power supply to power my laptop. I'm not looking for the PSU to charge my battery, the battery is almost useless now. I was thinking that the components of a PC PSU would be more robust than cheap knockoff chargers. The ventilation of a PSU would also mean that it would not overheat.

So my question is, how feasible is it to use a power supply to power a laptop? Is it implementable by someone who does not know a lot about electronics?
 
Solution
well, as greens said, it depends on your sparky ability. Normal PSU's for desktops don't output 18.5V dc, that the charger does, making straigth plug-in not feasible.
It also seems that HP has been selling that with both 90W and 120W bricks, using 90W brick could well cause a burn-out since laptop could be asking for more.
https://www.amazon.com/gp/product/B005553MD2/ref=pd_sbs_147_1?ie=UTF8&psc=1&refRID=D0ZCPQD0JCBQYQFZVHF9
Since the voltage, according to that is 18.5V DC, you could just cut out the brick and use something like...
https://www.amazon.com/Giantex-Supplies-Precision-Variable-Digital/dp/B01I6MPSPU/ref=sr_1_1?s=industrial&ie=UTF8&qid=1475166102&sr=1-1&keywords=power+supply+10A

As far as external power supply is concerned...

greens

Distinguished
Jan 27, 2012
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19,160
Uh depends. Should be theoretically doable depending on your sparky ability.

Then again, i don't think you get any 9v or 15v lines off of an ATX PSU, can't recall exactly.

It is NOT advised you simply mate wires to change voltages, it isn't safe. So really it would be more work and require more devices to accomplish.

You need a new power brick.
 

little_me

Estimable
May 9, 2015
151
3
4,910
well, as greens said, it depends on your sparky ability. Normal PSU's for desktops don't output 18.5V dc, that the charger does, making straigth plug-in not feasible.
It also seems that HP has been selling that with both 90W and 120W bricks, using 90W brick could well cause a burn-out since laptop could be asking for more.
https://www.amazon.com/gp/product/B005553MD2/ref=pd_sbs_147_1?ie=UTF8&psc=1&refRID=D0ZCPQD0JCBQYQFZVHF9
Since the voltage, according to that is 18.5V DC, you could just cut out the brick and use something like...
https://www.amazon.com/Giantex-Supplies-Precision-Variable-Digital/dp/B01I6MPSPU/ref=sr_1_1?s=industrial&ie=UTF8&qid=1475166102&sr=1-1&keywords=power+supply+10A

As far as external power supply is concerned, you don't really have much choice. 18.5V is not one of the standard 9, 12, 24, 48V values and Current amount that the brick wants 6.5A is higher than normal power supplies. Thus to prevent burn-out, the maximum current rating should be over that 6.5A

As greens said, I recommend sticking to "standard" bricks and failing that, going for big enough power supply that can supply it for sure.
 
Solution