Posted By: F9zDark
It would appear that the folks over at Infectus have made a PS3 downgrader, complete with tutorial on how to get it working. As of this writing there has been no documented case (that I have seen) of working and the overwhelming risk of brickage have turned many over at the Official Playstation Boards off to the idea.
To get started, you should download the small software that you can find HERE
Then, please download the Drivers that you'll need to make Infectus visible for the System Here
Once you have got everything turn your console ON, connect Infectus to the USB port and start the software!
show you how to READ and WRITE the internal NAND FLASH of PS3:
Here a nice video of this feature: