okay so define "checking out". Are you looking to buy the thing, or are you repairing it for someone else, or what.
Usually "no bootable device" means just that. Either there isn't a bootable hard drive installed or the boot data has been corrupted or deleted from it such that, even though in hardware terms there is a "bootable device", the operating system is missing or damaged such that the device will not boot.
The easiest way to make progress that I can think of is to make or otherwise acquire a bootable USB device with (example) Win7 on it, or Linux, or whatever and see if the computer will boot to that. If yes, then you probably have a hard drive problem, it's either missing, physically damaged or the operating system on it is damaged. If your bootable USB device will not boot, that indicates even more serious problems with the computer, example bad motherboard, power supply, video card, etc... i.e. hardware which is very bad.
I use "Rufus" to make my bootable devices and a Win7 ISO file I download from "somewhere". I think you can use a 16 Gbyte USB drive. Maybe even an 8 Gbyte. Not sure. They're cheap now. I think a 16 Gbyte at Walmart is about $12.00.
Edited by Aaron_Warrior, 24 May 2017 - 06:54 PM.