I've been running into connectivity issues with my Comcast Wifi internet lately on my PC and PC only.
My Wifi itself seems okay. The signal strength is excellent most of the time and we don't have many devices connected to it, just my PC, a Laptop and now my Kindle. The problem is I've been experiencing loading difficulty with webpages. This issue is not just localized to Firefox. It also affects Chrome. Even with full signal strength webpages sit through the loading process indefinitely, or even give me an authentication failure message. However, loading up the web browser on my Kindle gives me no problems loading webpages. This problem is sporadic. I have moments like this, but then it returns to "relative" normal again. Sometimes I've temporarily fixed the issue by changing my Wifi's Channel between 1, 6, and 11, however this rarely fixes and when it does fix the problem does return. For the most part now I've just set the Channel setting to automatic and dealt with this, using the internet when I can.
My adapter is a USB from Asus, an 802.11 b/g/n adapter because the Ralink one that came with my PC started to crap out on me horribly.
So, would this be a Router problem, Network problem, Adapter problem, or a Computer problem? I'm leaning towards computer.