I'm looking to power my Lenovo workstation-class 20V 170W (8.5A) laptop with at 12V supply. This is for efficiency purposes, so not looking to go the 12V DC-AC-DC route and would rather go DC-DC because I'm not just looking to power it in my car, but also with a portable 12V battery station. The problem is that I cannot seem to find a 12V to 20V step-up converter. The closest I have come is a 12V to 19V 15A converter and was wondering if the 19V would work with the laptop and converter (without causing overheating/overload in the converter). The 15A seems capable enough because the AC-DC converter is rated at 8.5A, but I am concerned about the lower-than rated voltage of 19V. Any thoughts? My first impression is that it would be fine, but don't want to drop the $$ unless I'm more certain.