Once in a while (nowadays more like a couple of times a day), I get the limited connectivity warning on my computer (yellow triangle with exclamation point), as do my parents' laptops (all wireless). My sister, on the other hand, uses a wired connection and she never has this issue. If I reset the router by turning the switch on and off, the issue is resolved, but it could happen again in a few hours or the next day. Also, this problem doesn't seem to occur when I'm actively using the internet, such as gaming or streaming, but when there's a lull in activity. What's happening?
Check your wireless card and make sure that the power management is not turned on. It would cause your wifi card to go into sleep mode in essence.
I'm not sure how to edit so I'm just going to reply.
I turned off power management and got the same issue today. During a game, no less, so you can scratch the activity part out of my original post. Interestingly, my sister (on the wired connection) got the issue as well. Also, your solution didn't account for the 2 other laptops with wireless connections having the same issue while the wired connection didn't previously.
Turn off everything including the router. Turn the router back on and wait for it to reset. Now turn on the computers one at a time. The computers should now grab new IP addresses to the router.