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I bought a new charger online when my old laptop charger stopped working. I ordered the new charger and when I was comparing the Voltage and Amps of the new one to the old I noiced the new chargers Amps were almost 2 higher than the old one (5.3A on the old and 7.9A on the new I believe I don't have the chargers w/ me at the moment). Also I noticed that the Input to the charger was slightly lower on the newer one. I used the new charger for about 2 days then the power brick melted (smoke plastic smell the whole nine yards) and I was wondering if the lower input on the charger or the higher output Amps had anything to do w/ the charger burning up or did it simply just get too hot and melted?

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Was probably just a cheap knockoff that self-destructed. Higher charging amps, very simply put, means it is "potentially" a stronger current flowing into your battery, but only if your battery is capable of "pulling" it. A charger does not "push" electricty, it simply makes it available for comsumption. The lower input voltage simply means that the charger "should" operate at that voltage and one that is marginally close to it(+/- 5%).

The main thing to look for in chargers is that the output Voltage is the same. If your battery charges at 14.7v, don't buy a replacement charger that runs at 18v. Amperage should be considered if it is grossly different, but for the most part it doesn't mean alot in this case. If a battery keeps 14.7v @ 4.8amps, it just won't use the extra amperage that the charger is capable of outputting.

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Agreed. From the description it sounds like a capacitor in the power brick did not like the load. Its also suspect that the output was higher then the previous model yet the input was less. (The other possibility, of-course, is the original charger was designed around 110 vols input and the new one 220 or vice versa, but I'd expect a switch mode power supply like that in a laptop to handle either input) – davidgo Feb 1 '13 at 20:33
Of course, the old charger may have failed due to a problem with the laptop, but a good charger should "protect" itself. – Daniel R Hicks Feb 1 '13 at 21:55

The melted charger is not up to You. The 2 Amps difference means that the new charger can provide higher demands of power than the old one.

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