The AC power adapter type cannot be determined. Your system will operate slower and the battery will not charge. Please connect a Dell 65W AC adapter or higher for best system operation.
Few weeks ago I started seeing this warning intermittantly when I connect the power adapter to my Dell XPS M1330. But for last few days it was very regular and I barely could charge the battery.
I called up Dell on Tuesday morning and since the laptop was on extended warranty (I need it with my kind of travel and usage), the scheduled a next day service. The guy showed up next day before 10am with a motherboard and a power supply. It turned out that Dell sent him a correct power cord (3-pin) for the adapter but wrong adapter (2-pin). So the technician was not able to test the adapter and had to change the mother board.
He was done in less than 30 minutes and when we put the power in, voila.. it was charging. But before he left, I tried twisting and rotating the power supplu few time and there was this warning again.
So I called him from the car and he called to FedEx me a new adapter next day. So I'm waiting for my new adapter which is supposed to come by 3pm today.
The technician said that there's a chip inside the adapter and in the laptop and generally he sees the problem with the motherboard if they are using a 3pin supply. An specially with m1330 as well.
So, in less than 2 years, this is the second mother board change and I'm off to my third motherboard already. First one was due to their famous GPU (display issue) problem.
Who know what'll happen in another 2 years.
