Third Party Power Adaptor Stopped Charging Laptop

[rjbinney]

I have a Dell Latitude D620 running Win XP SP3.

It has stopped charging its battery when plugged into my Kensington Universal 120W power adaptor (it runs off power, it simply does not charge).

When plugged into the OEM 90W adaptor, it charges fine.

I also receive an error message telling me that "The system will run slower and the battery will not charge. Please use a Dell 65W power supply for better operation." (Note that Dell supplied me with a 90W!).

This is true wherever it's plugged in; it's not local to an office, hotel, home, etc.

Here's what's strange:

This first began this Tuesday evening. It has operated correctly from the time I started using the Kensington (December 2007) until then.

The first time I noticed this, I rebooted the computer, and all was well again. The following day, the problem recurred, and has been continuously the case since.

I have tried System Restore, different batteries, updating the BIOS, but all seem to have no effect.

Today I tried the Kensington charger in a Dell Inspiron 6000 running XP SP2; it gave me the same error. I don't travel with the Inspiron, so I don't know if I've ever actually had it plugged into the Kensington before.

I have been told that Dell programs its motherboard to reject third party power supplies; that does not explain why it began this week and not before. I don't have enough data to narrow it down to something that might have changed around my Dell, or around my power adaptor...

Thanks for any suggestions...

[DaveLembke]

120watt adapter used on a 90watt laptop is not good.... the adapters all are rated for the load that they will be given. So a 90Watt 12 volt DC adapter for example would be fine for a laptop requiring 90watts, but a 120watt adapter rated at 12 volts DC will likely feed closer to 13 or 14 volts DC into the laptop if the Voltage Regulator in the adapter does not restrict the power output due to less of a load on the power divided from your wall outlet.

You could smoke your laptops charging unit due to the 30 watt difference which could over voltage the laptops charging unit.

But given the fact that your laptop is fine on the original 90watt adapter, but not well on the 120watt, it is possible that the 120watt adapter lost the battle by being incorrectly loaded ( in which your lucky ). If you were talking about a 100watt in place of a 90watt 10 watts wouldnt be as bad as a 30watt output difference.

Laptop power supplies ( ac adapters ) are different then internal PC power supplies in which you can have a 500watt supply for a system only requiring 350 watts. Far different architecture between a Switching Power Supply in a desktop computer and a laptops Drop Down AC/DC Transformer.

I'd buy a new adapter and get some closer to 90 watts, and no more than 100 watts to limit the over voltage potential due to insufficient draw.

[rjbinney]

Thanks.

Why, though, now?

And why does Dell tell me I need a 65W supply when the OEM is a 90W?

[rjbinney]

So here's the drill.

Kensington power brick does not charge either Dell running XP SP3 (machines in original post.) It powers them, but does not charge them.

This happens anywhere I try; at home, hotel rooms, anywhere I try.

Now, HERE'S WHAT'S INTERESTING.

The Kensington charged my Latitude just fine (in both USA and UK) from December 2007 (when I first used it) until November 2008. In November, I sporadically received the error message in my original post. Then, from December, until sometime this spring, I continuously received the error message (and no charging). Sometime in April, the Kensington resumed charging my laptop every time I used it. Until the last week of June. Now, it no longer works again.

There are no known changes to my setup. Same batteries, same outlets, same Kensington brick.

Any thoughts NOW?

Thanks!

[rjbinney]

bump