I recently fixed my PS3 YLOD and it works fine, I put Thermaltake TG-2 on both chips applying just a thin layer of thermal grease. So i turned it on and left it idle for 10-15 minutes, when i come back the fans were on full throttle, so im guessing if i did something wrong? I dont remember how it was after being fixed but i dont think it was like that. So anyone could help me? Maybe I need a little more thermal grease? I have a BC 80Gb Motorstorm pack.
It's possible that you don't have enough, but be careful not to just glob it on because that will have the same effect. When applying thermal grease, the best method is to first clean all of the old residue off of both the CPU/GPU and the heatsink using rubbing alcohol and a qtip. Then place a small dollop about the size of a BB in the center of each component. place the heatsink on the processors and slide it around to spread out the grease but be sure not to lift it back up. Reattach the heatsink to the motherboard and check it again. Hope this helps.
I had a similar issue with my YLOD ps3 which I was fixing every week or two. I saw this tip on a YouTube video and my PS3's been working for over a month now.
When you tighten down the heatsink plates, if you do not screw them down evenly, the heatsinks will not sit flush on the chips which may be the reason your fans are blowing hard.
What you want to try is turn the screws in about 3-4 turns each switching back and forth until they are tight instead of tightening down 1 screw at at time. This will help sit the heatsink flatter on the chips, hopefully, dissipating more heat.