Different charger to charge laptop.

[Cooneyboii]

Hi guys,
Just wondering can anything bad happen if i use a 20v, 3.25A charger for a 19V, 3.42A laptop.
The wattage turns out the same for both (65W). The Laptop is a Toshiba Portege R830 also the polarities are the same on the charger and the laptop.
Thanks,
Eoin

 

[the nerd 389]

No, I would not use that power brick. The voltage is different.

Basically, the voltage rating determines compatibility, and the amperage rating determines capacity. Running a higher voltage than normal will subject the laptop to conditions it's not equipped to handle. If you give a device more voltage than it is designed for, but still low enough to use, it will burn the excess as heat to bring the voltage down to something it can use internally. It will not get extra power from the additional voltage.

A higher current rating means that the supply is capable of delivering more current, but it doesn't mean that it WILL deliver more current. The laptop controls how much current it draws, and it will not draw more than it needs.

Just some examples:
19V, 3.5A : compatible
19V, 25A : compatible
19V, 3A : not compatible, insufficient current
20V, 3.25A : not compatible, potentially excessive voltage, insufficient current
20V, 3.5A : potentially compatible (75% chance), potentially a fire hazard (25% chance)
21V, 3.5A : potentially compatible (50% chance), potentially a fire hazard (50% chance)
22V, 3.5A : potentially compatible (25% chance), potentially a fire hazard (75% chance)

 

[clarkjd]

I wouldn't. you are over vollting and over currenting the laptop. Asking for a fire.

 

[the nerd 389]

I wouldn't. you are over vollting and over currenting the laptop. Asking for a fire.

Over-currenting isn't really a thing...

Any battery management system will limit the current that's drawn to the appropriate levels. That's a requirement for using lithium based batteries, as charging those takes two phases. One is constant voltage for the upper 40% of charging, and the other is constant current for the lower 60%.

 

[Cooneyboii]

I wouldn't. you are over vollting and over currenting the laptop. Asking for a fire.

It would be over-volting but under-currenting.

 

[Phillip Corcoran]

Still not advisable due to the over-volting issue alone, irrespective of the amps rating.

You came here for advice, you got consistent advice from three of us out of four replies - Don't use it.

(Unless you don't care what damage it might cause to the laptop)