I'm going to try to downgrade to a prior fw below 3.0 to see if it reloads/flashs the drive & laser fw back, just to check. If it lets you go all the way back to the release fw without eff'n ya, i'll do that and slowly upgrade the fw's. It's a shot in the dark, but i've got a little time to kill plus it would prove (if it corrects the problem) that Sony did screw up some peoples machines with a fw update - that would be huge and could possably launch a suit to have those machines fixed on the house.
You have to clean the controller on the new board and clean the BGA chip up from the old board before you can reattach to the new one. I mean I guess you dont have to, but your success rate is going to suffer.
So I downgraded all the way back to 2.0 from 3.41 and that worked out ok but still no BD spinup. So I was like *, well how low can you go, it's already broke. So I slaped a 2009 model with some 2006 firmware 1.02 (Ya thats right!) So low and behold the ps3 would not boot on the tv, but would spin the disk up... weird.
It gets stuck in that fw by the way and you have to re run your service loader then stick the fw you want it to use back in, and you can get out of it. But when you start bumping the firmware up back to something that shows up on the tv like 1.92 - It stops the spin up? Thats as far as I've gotten right now going to keep bumping it up and see if anything changes.
Thats pretty much where this is at right now - desolder/solder, but with this new Factory Service mode option, none of that would be needed. If it doesn't take to long to find the cex & dex.exe's, its the way to go.