On Windows 8, in the "Advanced Power Settings" (even though they're not that advanced), when you expand "Power buttons and lid," there is an option called "Sleep button action." Where is this "sleep button"? I can't find it anywhere on the laptop (a Dell Inspiron 15z) and when I search for it, not many people apparently care about it. Where is it?
Here are some pictures of places on the keyboard I think it might be: