My xbox 360 S model is freezing and trying to update over and over at startup. I was just using it two days ago and it worked perfectly, and now today it won't boot up. I tried to turn it on and it went through the xbox logo fine, then it got to the spinning circle and froze on that screen. So I restarted it a few times and got the same thing. Then i unplugged it for about an hour and tried again. This time it asked me to update. I said yes and it turn off the screen completely (my TV said "check signal cable", which is what it says when nothing is connected), but the system was still on. 30 seconds or so later the system came back to the xbox logo and tried to start again, this time just going to the spinning circle and freezing again. I tried again and it asked me to update again, this time when I clicked yes it started updating. I finished the update and it restarted and asked me to update again. Now whenever I try it, it either freezes, asks to update then freezes, completes the update and freezes, or completes the update, or lets me into the dashboard for about 5 seconds and then freezes.
Another thing to note is when the spinning circle is there, there are a few odd pixilated squares on the screen. Not sure what to do, The update doesn't seem to be staying, is there a way to manually reset the cache, or is there anything else I can do to fix this?