I am using debian stretch on some of my computer for about a month now. It works pretty well, but I have a problem when using my Hp DV6. Even if Ihave installed the wifi driver for my ralink rt-3290, (the firmware-ralink package) the wifi worked once, and after reboot is not available. sometimes, after five or six reboot it works for a time but stopped within hours. When I try to find the problem, the cards seems here and available, the correct driver is still working but wifi doesn't. I don't really know where to look for something else, and I didn't find any thread about that anywhere. Please excuse my english, am not really fluent... 
Trouble with Ralink RT-3290 on Debian : Works when it wants
debian;wifi