My guess, regarding your son's laptop, is that the battery is dead. If you have same model, or your laptop uses same model of battery, then you could try your battery in his laptop to see if it works.
FYI, battery's life-spawn is very limited. No virus can kill it.
If you suspect trojans and viruses on any machine, easy and simple way, but potentially dangerous way would be Combofix. Just google it, download it (save it somewhere) and run it.
I must stress that it is potentially dangerous because it could corrupt windows registry and thus render it unbootable. You would be forced to restore your system, or reinstall windows...
Believe me, where other AV software failed, combofix prevailed. It cleaned my system from one very nasty trojan (vundo).
Edit: LOL
Chaky
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You swapped the charger..ok.. But, I'm talking about batteries. You should swap the batteries.
Dead battery + OK charger = dead laptop (with no-power-at-all appearance).
Edit was a comment on post before mine.. you got 2 almost the same answers at almost the same time.
Chaky
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htf do I swap the batteries?
Can do with sons/mine as they are the same but what are the risks, if any?
You should consult with the manual on that.
There are virtually no risks, if the battery has no acidy leaks.
Chaky
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This is definitely techies job now. If the warranty is still valid, it will be free of charge (heh). If not, at least you now know that it is not the motherboard or CPU that needs replacing.
Chaky
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Is the battery from your son's notebook charging OK in your notebook?
Chaky
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