This article show how a guy fixed his Apple ibook which had a gfx card fault. This is very common , 5 people i know had ibooks fails this way.
http://geektechnique.org/projectlab/726/diy-obsolete-ibook-logic-board-repair?commented=1#c003228
The interesting thing is that this is exactl the same fault as the 360 suffer from. A BGA grib array coming unstuck, i.e the solder connection breaking. The guy fixed it simply buy stripping the mobob down and place a metal container full off pure alcohol of top and lighting it. The heat is enough to remelt the solder yet not hot enough to cause damage. Other people have tried heat guns and had no luck.
I know MS have just extened the warranty on all 360s however if you have hacked you box so you cant send it back this may well be a very viable way of fixing the unit.
http://geektechnique.org/projectlab/726/diy-obsolete-ibook-logic-board-repair?commented=1#c003228
The interesting thing is that this is exactl the same fault as the 360 suffer from. A BGA grib array coming unstuck, i.e the solder connection breaking. The guy fixed it simply buy stripping the mobob down and place a metal container full off pure alcohol of top and lighting it. The heat is enough to remelt the solder yet not hot enough to cause damage. Other people have tried heat guns and had no luck.
I know MS have just extened the warranty on all 360s however if you have hacked you box so you cant send it back this may well be a very viable way of fixing the unit.