It's a good thing you have it under warranty still. Definitely send that in. I opened mine up and fixed it myself before I realized it was under warranty. By the way, the primary cause of RROD has to do with the lead-free solder they use. Lead-free solder isn't very temperature resistent and is more brittle then regular solder. As a result, constant temperature changes can cause the solder to become more brittle, and eventually crack(for lack of a better word) causing cold solder connections. So its not that the 360 has overheating problems, its that it wasn't properly designed to handle the heat it puts out. A PS3 at the same temperature would be fine
If this should ever happen again while your 360 isn't under warranty, there are a few ways to fix it. But I must urge you, DO NOT DO THE TOWEL TRICK!! It will temporarily fix RROD yes... however, in the long run it only makes the 360 worse and is ALWAYS only a (very)temporary solution. The way the towel trick works is by causing the 360 to reach beyond its normal "overheat" temperature, this causes the cold solder points to become softer and even melt a together a little, causing the connection to be restored. There is a better way to overheat your 360 though. You take it apart(use google to figure out how), remove the heatsink, dvd drive, fans, etc... then plug in the AV and power supply and turn it on. It should flash the RROD. You leave it on for 30-45 mins and it should overheat causing it to flash 2 lights instead of 3(that means its overheating). At this point, it's not at a temperature level which is dangerous for the 360, however it is approaching that temperature, so turn it off. The power button might not work for turning it off, so just unplug the power supply(and AV while your at it). Then let it cool off for approximately 30 mins(untill its room temperature). Put it back together, and you have a working 360 again. However, like the towel trick(since it accomplishes the same exact thing just safer...) its only a temporary solution.
There are various methods which are helpfull for preventing RROD from coming back. One such method is the X-Clamp trick. On the bottom of the mobo(motherboard) there are 2 pieces of metal shaped like X's. You remove them, take off the old thermal compound, put on new thermal compound(preferably Artic Silver). and instead of putting the X-Clamps back on, you replace them with screws and washers. youtube x clamp fix for more info.
Another decent method is the penny trick. Now, many people will tell you that the penny trick does not work/is bad for your 360 etc... Do not listen to them. The only way its bad for your 360 is if you overtighten the screws and fracture the mobo. And the reason most people think it doesn't work is because they didn't mess with it enough. It usually does require a bit of fiddling with things to get it working. But basically... on the underside of the mobo(where the x-clamps are) there are little black chips(the RAM). There is a good chance they have thermal pads on them(little white/pink foam pads). There should be 4 of them in all. So what you do is take 4 stacks of 3 pennies(Some people can't get it to work with stacks of 3 but can get it to work with stacks of 2). Wrap them in electrical tape(or something better if you have it, but chances are electrical tape is probably the best you'll have to work with. Just wrap it around the pennies once verticle and another time horizontal. Pinch the corners together so that the pennies are not visible. Then you attack the pennies to the ram. There are a few methods of doing this. My favorite is to remove the thermal pads, remove the pink part so that it's adhesive on both sides, and use the thermal pads to stick the pennies on. Make sure to press firmly on it when trying to make it stick. You then put your 360 back together and it should (hopefully) work. If it doesn't, don't fret. Try readjusting the pennies and tightness of the screws(and make sure all your screws are in. It usually won't work otherwise) The way this works is by more evenly distrubting the pressure from the screws across the mobo(I'm pretty sure). As a result it pushes the cold solder points together. If you manage to get it to work, but your fan is going crazy(hyper fan) then changing the tightness of the screws should be able to help. This method can be long and tedious to get working right, but I believe it to be the most permanent fix short of resoldering it or buying a new 360. For more info, google penny trick and look for forums discussing it. Watching tutorial vids is nice and all, but feedback from people attempting it is much more valuable.
Another thing that helps(even though it wont actually "fix" the RROD) is to take some foil and cover about 1/3 to 1/2 of the heatsink with it so that more air gets directed towards the GPU without actually disrupting the normal flow of air. Youtube xbox 360 foil trick for more info.
And thats about it. There are other methods, but of all the ones I've tried, I've found those ones to be the most helpfull.
While your 360 is open(meaning your warranty is void)... You might as well take this opportunity to flash the dvd drive so that you can play burned games. I will not share exactly how to do this here, but I will say that if you have a BenQ drive in your 360, this is a walk in the park to do. You just have to be extremely careful to make sure your games are stealth patched and all that fun stuff(there are programs for handling this)
One last word of caution. DO NOT CONNECT YOUR 360 TO XBOX LIVE untill you are sure everything is connected properly and put together. To be more specific, if the dvd drive is not connected properly and you attempt to connect to Xbox Live, your 360 will be banned from live play(Not might.... will)
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2101729 Kalantir-Bar-Orc-Mal-Cha escaped the dungeon