About Smart Laptop AC Adapter?

We get this inquiry all the time: Someone purchases a replace adapter for their Hewlett Packard laptop. The recommended replacement is an HP Pavilion zt3223 AC Adapter. This comes from HP’s own compatibility site. But the customer’s laptop requirement and the old adapter are both 65 watts. So of course we get a call saying “What gives? You sent me the wrong adapter!” Even with a plethora of explanation we still get some resistance for fear of burning up a $1,000 laptop.
How does this work?
The “smart” part of smart adapter is that HP has engineered these so they can accommodate the power requirements of numerous HP laptops. So for the laptop requiring 65 watts, the adapter self regulates and puts out 65 watts, for 90 watt requirement it puts out 90 watts. And while it’s not optimal, I’ve even seen 90 watt smart adapters accommodate 120 watt requirements. Of course it had a tough time both powering the laptop and re-charging the battery simultaneously but it was able to do in a pinch. However,I don’t recommend this mix.
Adapter , adapters
To match up with the wide range of HP laptops and their varying power portal sizes, HP made the tip size (part inserted into the computer) as universal as possible then offers a series of tip adapters known by the interesting name of “dongles”. (Who came up with that one?) So when HP recommends a Smart IBM AC adapters that is outside the range of what you might consider a safe wattage for your computer, they aren’t trying to fry your laptop so you’ll purchase a new one, they have just consolidated the replacement options using a little bit of engineering and a dongle or two.