I was trying to find a slim power adapter for my Precision 3520 with Xeon processors. I ordered the 90-watt power adapter since the slim 130-watt adapter has a 4.5 mm connector.
I powered up the laptop and received a warning message that the 90-watt isn't enough (the laptop came with this wonky 130-watt adapter that is pretty big). I ended up ordering a 130-watt adapter with 4.5 mm connector and I'm waiting on a 4.5-7 mm adapter to get here to make it work.
Today I thought I would try it out. I hooked the 90-watt adapter up with the battery at 80%, opened up Kaspersky and started a full scan while also performing a backup, opened up the Netflix app and started streaming a movie, then opened up Philips SpeechExec Pro to transcribe with Dragon Medical Practice Edition in addition to the following apps: IE, Edge, Outlook/Word/PowerPoint/Excel/OneNote 2016, Sonos, Pandora, Amazon Music, Weather, Weather Channel, iTunes, Dropbox. I was connected to an external monitor via HDMI and had the laptop lid open so the built-in screen was also on.
The 90-watt adapter was more than enough, although the charge took a long time to get to 100%.
I'm posting this in case anyone else is wanting a slim power adapter instead of the large one that comes with the laptop. Google searches didn't find anything productive, so hopefully this will show up for anyone interested and that Googles it.