Thank you for such a thorough reply. I would prefer to have the features provided by x1.2Opt. Also, thank you for the notebook suggestions, but it doesn't seem like any of those models support more than 16 GB of RAM. It looks like it is possible to disable dGPU in W520 according to this W520 bios emulator: http://service.lenovo.partner-management.com/content/CoursewarePublic/15418/W520.swf Do you think it would do the trick? I saw a couple of W520 owners' forum postings saying that they had to use setup 1.1x, but that was in 2011 and before Lenovo released the bios fix for the tolud issue.