My laptop's charger was not working anymore. So I bought a new one. However I couldn't find an exact matching charger, I bought a different one. My question is; Will there be any problems with new charger? Specifications of chargers are below;
Original charger: 65W, input: 100-240V, 1.6A, 50-60 Hz, output: 18.5V, 3.5A
The new one I bought: 90W, input: 100-240V, 1.5A, 50-60Hz, output: 19V, 4.74A
Without knowing the specs of the laptop in question, the answer is maybe.
Depending on the laptop's tolerance for voltage variance, 19V is likely within the safe zone (plus or minus 5%, a typical tolerance, gives you a "safe" range between 17.575V and 19.425V).
The device will only draw as much current as it needs, so as long as the replacement charger has an amperage rating greater than or equal to the old charger, it should be fine.
However, even assuming both of those are OK, it's likely that if you run into issues, your laptop's manufacturer won't cover it under any warranty. It's also possible that the laptop will refuse to charge or only charge at a lower rate if it can't ID the charger (an OEM charger may have a chip in it that allow it to communicate with the laptop that the replacement won't support).
P (wattage) = V (voltage) * I (amperage) Using the adapters in the original question, 18.5V * 3.5A = 64.75W, 19V * 4.74A = 90.06W. So yes, assuming the voltage and amperage are fine, wattage will likely be equal or greater, which is also fine. The voltage and amperage are the more important numbers, though, as you can get similar wattages with wildly different amperages and/or voltages.
The voltages have to match, more or less. 18.5 versus 19.0 should be fine since 11.5 vs 12.0 is fine for a desktop PC (rule is generally 5% variance).
Current (amps) must be equal or higher on the charger, and the closer they match the hotter (generally speaking) and less efficiently the charger will run.
