I'm trying to install 16.04 Ubuntu Mate using the mini.iso on a ThinkPad T450s. However, when I get to the initial menu and select "install", the screen goes black without any further activity. The installation process never begins. I've also tried "command-line install" with the same result. I have the machine set to legacy boot (uefi doesn't even get me to the menu), secure boot is disabled, and I've checked everything else I can think of that might be preventing things from working. I know the usb is fine because I've used it to successfully install the same OS on a T60.
Any help would be appreciated.