another cause of YLOD or (atleast why the ps3 overheats)
I was working on another unit of PS3 (PHAT) for reballing last week. The problem was that the ps3 fan goes to the last speed level in just 1 minute. Ladies and Gentlemen, the PS3 Jet is about to take off, please wear your seat belts. LOL.
The repair process begins.
When I lifted the fan and the heatsink, I said, WTF, the thermal compound was about a size of a quarter in the middle of the RSX and CELL. So I tried to apply some CDRking Gold Thermal Paste (This is great stuff by the way) using the X-Method and when I tested, it had the same symptom.
OK I was thinking that I might have made a mistake so I tried again and I'm getting the same results. I've always applied the exact amount needed when applying thermal paste on cores so I was wondering what was going on.
So I tried the Credit Card Method.
Apply a straight line at one of the four sides and use the card to spread it all over the core. Guess what. Same Results. But this time, when I lifted the Heatsink, I made a discovery.
The heatspreader on the RSX and the CELL are NOT FLAT. Yup, there was no contact in the middle (Where the core is supposed to be). It was all four corners for the RSX, as for the Cell, only 1/4th of the Heatsink comes into contact to the heatspreader.
I sanded down the heatspreaders to a tolerable flatness, Polished using Buffing Tool, applied Thermal compound using the X method, and viola, 30 minutes until full fan speed, no overheating.
I informed the customer about it and instead of charging for the repair, he gave me $$$ and I water cooled the ps3, installed LED heat indicators, and bought a cup of Starbucks Venti Frappe while waiting for the unit to be picked up.
Photos to follow.
I checked the PS3 slim too (So much for warranty) and the case was the same, the heatspreader for the RSX was not flat enough (Same symptom, only four corners are in contact with the heatsink), but the CELL is different, the heatspreader is a bit thin so I dont think Sanding it down will be a good idea. I applied AS5 this time and I'll leave it to set for a week before using it. (AS 5 setting time is 200-300 hours) (CDRKing Gold Thermal Paste Setting Time varies on viscousity but has the nearest heat transfer characteristics as AS5, good for Trial and error).
Without further adieu, here are the photos.
Below is an image of the CPU/CELL of a ps3 SLIM. The areas selected in red are the only areas that make contact with the heatsink. not even 20% of the area. phew.
Below is an image of the GPU/RSX of a ps3 SLIM. The areas selected in red are the only areas that make contact with the heatsink. Even lesser contact. HELLO YLOD.
Below is an image of the CPU/CELL of a ps3 Classic/PHAT. As you can see, most of the areas are not in contact with the heatsink. In this image, the core should be at the center of the heat spreader but most of the contact is not here.
Lo and Behold! Welcome YLOD. Yes, as you may have guessed, this is the RSX chip of the PS3 Classic/PHAT. The important area which is the middle is what gets hot really quick. Tsk, now wonder 500,000 or so of PS3 Classics are affected by the YLOD.
You see, Unlike MS's Xbox, $ony's mistake is not necessarily the Solder that they use. Engineers design this expecting that the flatness would be near Zero, but this ain't near Zero, this is way beyond 0.5mm.
Why would I say that it's not the type of solder? Why do people in youtube target the GPU first before the CPU? Did you know that in both the XBOX and the PS3, the CPU gets hot the most? nah, didn't think so. It made me wonder the first time I got a jtag and I finally got the answer.
People who own a jtag Xbox will be able to see the huge difference (about 10 degrees) in temperature. So why does the Solder on the GPU bridge/disconnect? For the PS3, poor thermal transfer, and for the xbox, board flexing.
Other than flatness, roughness is also a problem. $ony decided to use Copper Heat spreaders and coat them with some type of alloy to allow etching the labels and prevent corrosion. Nevertheless, it's time to go linish your units, especially if your beyond your warranty period. Replacing the thermal compound will not do the job, time for a permanent fix!
Btw, I did the sanding manually, and used a buffing tool to achieve a tolerable smoothness. Photos of polished metal to follow...