2007 XBOX 360 was overheating. Red ring of death - 3 red lights.
Tried repairing by applying just arctic silver but only worked with the cover off, so I bought the kit - with the extra heat sinks etc...Followed the instructions and did the reflow too with a heat gun. All is well - has been working fine since.
Take your time and follow every step. Make sure you clean the chips and only apply a little arctic silver.