I got this cheap square wave cigarette adaptor at Walmart and then read lousy reviews about it tripping when people powered up their Laptops. It was ok for
charging but not running. It is a Cyber Power 2 in 1 inverter.
But my Toshiba only uses 90 watts and the unit is for 140 watts cont.
Could it be so off that it wont even run 90 watts???
Or do you think some laptops use a lot more than mine..??
and I know I can return it like 50% of what I buy at that crap box store..

 

I got a similar POS for $8 and found that it makes a square wave of a lot less than the peak voltage of a housepower sine wave. Not even a stepped square wave! I can't imagine this thing providing proper voltages to drive something that's expecting a 115 VAC sine wave. Sometimes you get what you pay for, and $8 is not the price of a sine wave.

 

it was 30 and it does work... wish I could see the wave though..