Weight difference in power adapters

Background, I like ultralight stuff. I bike around a bunch, less weight means I'm not so annoyed all the time. After two years of running Apple crap I'm finally switching back to Debian.

So I've ordered an X220, comes with the generic power adapter, isn't here yet. Off of ebay I grabbed one of the 90w Lenovo Ultraslim chargers. By simply holding the charger and associated cables to only charge the laptop and comparing it to the smaller charger that my T41 is currently plugged into, it seems like the Ultraslim charger is actually heavier.

Has anyone done any weight comparison between chargers? I also just spied the Targus Compact Laptop charger, which seems like it might be a slightly better package, except if I'm touring around somewhere without US plugs (like the EU) it would kind of suck without an extension cord.

Did I just make a mistake burning $50 on what I thought would be a lighter charger?

 

The UltraSlim 90W charger is lighter/smaller than the stock Lenovo 90W charger. The X220, however, comes with the smaller 65W AC adapter--since I don't own the UltraSlim 90W charger, I can't say how it compares to the 65W adapter, but the 65W is a fair bit lighter and smaller than the 90W.

 

I haven't got the Lenovo ultraslim but you are probably right about it being heaver. 90W requires more powerful electronics and the amount of plastic casing is more. I have a similar Dell device (but only 65W rating) and one of its advantages was that it used a 2 pin connector for the mains lead so the mains power cable was thin and light.

My T420s came with a 65W PSU and 1m mains cable that together weighed 0.35kg (0.77lb). However, my annoyance is that it used a 3 pin mains connector which means bulky and heavier mains cable while 1m is too short to be versatile. Happily, one day I came across an adaptor to connect a 2 core mains cable to 3 pin socket so I can now use a thin, flexible and longer mains lead with my Lenovo PSU.

John

 

I would recommend not doing that unless you are sure the power supply does not use the ground circuit at all. I do note the US power supplies don't use a grounded plug, but they also only use a 2 pin socket.

 

There's not much benefit of carrying around a grounded cable to then plug it in to an ungrounded socket or worse (and I've come across this) the socket has a ground wire which carries a voltage because of leakage from other connected equipment but the wiring itself isn't properly grounded.

John

 

http://msinetpub.vo.llnwd.net/d1/keithcombs/blog/images/w520/brick_bottom.jpg (1.2mb)

(Source: Keith Combs).

 

Just got my machine. By simply holding the bricks it's pretty obvious the stock 65W charger weighs less than the Unltraslim one, especially with the extremely thick cables.

Oh well.