I had my phat 360 fixed 3 times, and each time it lasted average 3 months.
I eventually gave up and bought a slim and I have had no issues.
Still considering reballing the phat, but don't know if its a guaranteed fix for the price you pay?
If it's been fixed before many times then a reball is pointless (motherboard is warped, GPU {possibly CPU} and connecting solder pads underneath are damaged). Vast majority of the repairers out there are heat-gunning and killing the mainboard in the process ...
I'm not plugging reballing for the sake of it BUT these DIY fixes do more damage than good - be it Xbox or PS3.
Reason(s) DIY fix is poor for the Xbox:
-the screws and washers stresses the heat-sink mounts on the mainboard
- curves the GPU / CPU causing hairline cracks on the BGA package (the processor is coated with a fibreglass like substance) - essentially breaking the processor
- squeezes the solder balls and solder pads unnaturally which causes damage - remember reballing involves removing the BGA package (GPU in most cases) from the m/board and what a cheap fix mainly causes is for a connecting pad to be lifted causing dead spots on the mainboard and permanently disconnecting an electrical connection. In other words, enough pads are missing the console won't boot ever
- uncontrolled heat causes the mainboard to warp and the processors to be scorched. Just a reflow needs to be done properly with a reflow profile which is done in stages until 217-220C is reached which is the liquidous temp of the lead-free solder used in manufacturing. This proper process cannot be replicated with a heat-gun or disconnecting the fan and waiting for 2 red lights like in any of the online tutorials. Not that a reflow is long-term fix in any case ...
And I can go on ... I started reballing in 2010 and was the first to make the service available to the general public for Xbox 360/PS3 locally. In that time I've spent countless hours trying to revive various grades of previously fixed units. The headaches have been far too many to mention ...
In regards to longevity as spoken about above ... if its a virgin 'light of death' then you're definitely going beyond 6 months. Once reballed the leaded solder applied doesn't crack again because it's malleable BUT the GPU dies. So if a client returns to me (which is minimal numbers) out-of-warranty and the error is GPU related then it gets replaced with a reconditioned one. I have a reliable overseas supplier --> This is only for untouched consoles before arriving at our premises as such BGA repairs I can guarantee.
The various local blog articles and comments on local forums attest to the quality of my workmanship. Once I've expanded my staff complement some more then laptop reballing will be tackled as that is another device where poor repairs are done.