Im sorry to hear your having a problem with your Ps3. In your description you said you've tried resetting the video settings by this do you mean the following?
While the PS3 is off, press and hold the power button until you get a second beep, then release the button. This should reset your PS3 to use whatever component cables are connected. This is necessary when you change component cables, especially when you switch from HDMI to regular cables.
If you have tried this and nothing happened you could try the following:
The following recovery mode allows you to fix many issues (both for the normal and slim versions of the PS3).
To access this recovery mode, follow the below procedure:
Turn off your Playstation 3 (the red LED is still turned on).
Hold the power button down, to completely turn off your console.
Keep holding the power button down until you hear a beep followed by 2 consecutive beeps.
You will be prompted to plug in your controller via USB.
Press the PS button and the Recovery menu will pop up.
Once in recovery mode select " restore the system files" this option will fix any errors occurring due to corrupted data.
After words make sure your ps3 is up to date by selecting SYSTEM UPDATE in recovery mode.
If all else fails your best bet is to back up your data and throw a new hard drive.
I hope I was able to help you and if you have any questions fill free to contact me at email@example.com
Devin A. Stokes
DexTech IT Solutions