Rodney Myrvaagnes wrote
I have never had trouble getting a 12-V charger for any laptop. I have
used NEC, IBM, and Toshiba.

I have a recent vintage Hewlett-Pacard Pavilion ZE series laptop with
an HP supplied 90 watt AC wall wart. I wanted to run off 12v DC so
called HP support and asked about an "airline adapter" (computer
geek-speak for a 12v power convertor). He said they don't make one
for the Pavilion series and recommended I not use an aftermarket
convertor, because none of them are rated for 90 watts, and typically
12v power sources aren't rated for 8 amps continuous on planes, etc.

He said the Pavilion's are power hungry workstation substitutes and
not meant to use 12v, and that I should get an invertor of the proper
size if I really had to run off 12v.

Oh well . . .