While it’s generally not recommended, you can use a 19V charger for your 19.5 v Laptop. Usually, too much or too little voltage can be a big problem, but a 0.5 difference in Volts hardly matters. Voltage calculations are notoriously imprecise, so your 19-volt charger may provide enough power for your device.
However, there are a dozen other factors to consider if you’re using a 19 V charger for your computer.
Things to keep in mind when choosing a replacement charger
Voltage is only one-fourth of the equation. You also have to consider the charger polarity, fitting, and current when shopping. Ideally, you want to replicate all of the specs of your former charger.
If you can hit all of them precisely, then you should come close enough that it shouldn’t make much of a difference.
Polarity: It is arguably the most important and easiest feature to get right. You can be certain of what type of polarity your laptop charger has by checking the symbol on your charger.
If you mix the symbols up and buy the wrong charger, you risk reversing the polarities and seriously damaging your Laptop.
Fitting: Finding the right fitting for your computer is simple enough. All you have to do is ensure your old charger’s connector matches your current chargers’. A loose fitting will cause inopportune disconnections, slow/faulty charging, and other problems.
Current: Ideally, you want the current output by your charger to match or surpass the power requirement for your computer. Most computers come with automatic regulators, which allow them to take only the power they need and leave the rest.
Having too much current will not harm your computer. Too little can cause a sharp performance decrease, malfunctions, and other long-term consequences.
Losing your Warranty
Another major risk of using a 19v charger for a 19.5V laptop is warranty nullification for both the Laptop and charger.
Using a separate charger for your laptop, especially one with a lower Voltage than recommended by the OEM is usually grounds for warranty cancellation. While that might not be a big deal if you use a computer several years old, it can be a serious problem if you sunk a few thousand dollars into a work computer that is only a few months old.
In this case, it might be smarter to buy a replacement from the OEM and risk using the lower Voltage charger for a few days (even if it shouldn’t cause any damage.)
As for your charger warranty, the store or third-party manufacturer that sold it to you might not void your warranty and refuse to offer a replacement for your product if it’s damaged.
Strictly, you should use chargers for computers they’re designated for and vice versa.
Using a 19v charger on your 19.5v laptop is relatively safe as long as you know your computer limits. There’s some risk to using an undervolted charger, but you should not run into any serious complications.
A slightly less powerful charger is especially fine if you’re using it as a backup charger for your computer.
Will a charger with a lower voltage cause my Laptop to charge more slowly?
Possibly. If the difference is as little as half a voltage, your computer’s high-precision voltage regulator should make up for the difference. If there are more than enough Amps or current, you won’t experience any sag, lag, or overheating issues.
However, if there isn’t and you’re doing some heavy computing or something just as demanding, the charger might eventually heat up and short circuit. If you’re using a charger from a trusted brand, you’ll trip the security fuse long before this happens.
Can I use an 18.5V charger for my 19.5V laptop?
1 volt of power is a bigger difference, and you’ll run into different results depending on the product manufacturer. Hp and Dell laptops will function with a charger 1 volt under, but you’ll get trickle charging, which could become a complete nightmare if you ever need to do some serious work.
However, low-end Asus computers don’t seem to be affected as much. It could be because of better optimization, or the manufacturers are more sensitive to their users’ needs. Either way, we don’t advise you to use an undervolted charger for too long.
Can it be dangerous to use the wrong charger for your computer?
A general rule is that your computer needs -10 or +10% wattage to operate. Higher than 10% works fine as your computer can run at maximum capacity without blowing out the charger. A charger with a higher wattage or Volt than your PC max load will also last longer than lower wattage alternatives.
Lower than 10% of the recommended power, your computer might come, but not charge. Prolonged use will cause the charger to overheat and damage your PC if you’re not careful.
How to find the best charger for your computer?
Always start shopping with the OEM and third-party manufacturers, trying to see if you can locate an exact high-quality match.
If you can’t wait for some reason, then check E-bay or Amazon. Both locations might have chargers made available by sellers who might have previously dealt with your exotic computer.