Things You'll Need
Instructions
Back up all the data on your 20GB PS3 hard drive. You can do this by connecting an external hard drive or a USB flash drive to the USB port of the device and using the PlayStation back up utility, available under the system menu.
Turn off and unplug the PS3 once the backup is complete. Leaving the console plugged in could present some danger of electric shock.
Remove the hard drive cover panel, clearly marked and located on the the left side of the system. There's a narrow notch on right side of the panel, which you can slip the edge of a coin or flat-head screwdriver into to aid the removal.
Remove the blue center screw from the hard drive tray using a Philips-head screwdriver. Once the screw has been removed, use the metal handle to remove the hard drive tray.
Unscrew the four screws on the sides of the hard drive tray; there should be two on the left side and two on the right side, located at the four corners of the panel. Once removed, set the screws safely aside and slide the old hard drive out of the tray.
Insert the new hard drive into the tray and replace the four screws to secure the hard drive. If your screws aren't lining up, this means that your hard drive is not aligned properly in the tray.
Push the hard drive tray back into the PS3 once the hard drive has been secured in the tray, and replace the blue center screw to secure the tray in the hard drive. Replace the plastic panel back over the hard drive.
Download the most recent PS3 firmware from the website, and save it to a flash drive, external hard drive or burn it to a disc. You will have to create a folder called "PS3," with a folder called "UPDATE" within that folder, both in all caps. Save the firmware file as "PS3UPDAT.PUP."
Turn on the PS3, insert the media containing the system update into the PS3, and follow the on-screen prompts for installing the firmware.
Use the back up utility to restore your PS3 files once the system is booted and running properly.