haha thanks a lot. I totally understand now. It's easier to find good 12.5A or 18A ac adaptor.

Can picoPSU-120 work with 19V + 7.9A power brick? I checked the manual: "Input Requirements: 12V regulated, min=2A, max=10A (load dependent). Over-voltage shutdown will occur at ~13-13.5V. " Is there any problem if I connect a 19V power brick to picoPSU-12? How about if I connect to a 12V 18A or 12....

Thanks for the reply. I still got some more questions: 1. Why 90W only if I use 2.5mm plug? So I can't use a 150W ac adaptor if I use 2.5mm plug? 2. Will you send me the P4 connector as well? Am I need to DIY the cable by myself? 3. What's the diameter of the 4 pin din connector? Is it 2.5mm? Thanks

I got a question, if my itx case can only allow me to plug a 2.5mm dc jack, can your extension cable fit it?