Canadian A740 AC /DC Adapter Charger CAD$45.95

Question about A740 laptop ac Adapter ( From internet ):

How do you fix a laptop charger that won't work?

Can be, but not limited to these conditions: 1) Charger is bad / dead. 2) Charger cord have internal disconnection (2 seperate parts). 3) Laptop Charging Port have some loose connection/issues. 4) Battery needs to change. 5) Different brand charger used. 6) May be there is no power in the socket you connected.

If my laptop is rated "19.5V - 3.34A / 4.62A", should I buy a 65W or a 90W AC adapter?

Wattage is Volts x Amps, but there’s more to it than this.

Excessive voltage can damage your device, but excessive amperage won’t (the device will only draw as many amps as it needs)

Therefore, you need to ensure that the charger you get is 19.5V. The issue then is, does your specific laptop use the 3.34amps or the 4.62? If you aren’t sure and cost is the same, just go for the higher amperage (therefore wattage) one. As long as the volts are correct, you wont damage the device.

I have a couple of Lenovo laptop with similar ratings and also 2 adapters available.

The reason is probably size and weight for portable vs. fixed location use - using a smaller adapter will enable CPU throttling and a couple of other power management features thereby reducing heat dissipation.

If size and weight of the adapter and added computer heat makes no difference to you, then buy the larger one and your computer will be able to operate at full performance.

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