How to fix this problem myself... the console is getting the 3 red lights of death..

Step 1 is to unplug every connection (component cables, PSU) from the console and power outlets for about 60 seconds, plug it all back in, and see if that makes any difference. Honestly it probably won't have any effect, but that is the first thing MS says to do when the Red Ring of Death appears. If that doesn't work, it's probably a loose contact point for the GPU or CPU causing the RRoD.

Is the warranty still valid? Even if your 360 is modded, if you have an in-store warranty at places like Wal-Mart, there is a chance they will not check under the faceplate to see if the warranty sticker is still intact. If you do have an in-store warranty, by all means try exchanging it. Of course if they check under the faceplate and see the warranty sticker all bubbled (from tearing it off) or missing, then you're SOL.

You could try the heatgun method. If that doesn't work, it may not be fixable. It requires a bit of ingenuity, and is not for the feint of heart. If you have a decent amount of tech saavy, you can probably pull it off. Most likely, a contact point around your GPU or GPU has come loose due to frequent use and the 360's poor heat dissipation scheme. If that's the case, you can try the X-Clamp replacement. The parts required for it are pretty cheap, far cheaper than getting a new 360. Here is a guide for the X-Clamp replacement.

Xbox 360 – X Clamp Replacement

The second link in particular is pretty good. If you personally can't pull it off, then it's worth looking around to try and find someone who can. Parts and labor won't cost you much.

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