The power supply is working properly with my notebook. (Asus Transformer Book Flip TP500LA-DN041H) Even the operation with 12 V is very good! However, the 12 V connection is 8.33 A (8.33 amps) continuous current and 100W stand or it may lead to overheating. Therefore, use only with a matching cigarette lighter connector and suitable cable! Calculation example: 100W / 12V = 8,33A Luckily my cigarette lighter connector supports 15 A continuous current. But many cigarette lighter ports of older cars hold only 8 A (8 amperes) of a short time and 4 Amps continuous. Everyone needs to know how much power endures his cigarette lighter connector itself. Each used the something does not add up is your own fault. The bad reviews, so I can not agree. The output voltage of the power supply is quite stable and that's good! The only thing that is slightly uncomfortable, the heat generation of about 50 C vollaßt In. But that is still in reasonable range. For the good price-performance ratio I give 5 stars.