Need help troubleshooting

I’ve been messing around with this ps3 I got from a friend for a couple days. I can’t get anything to display on the tv no matter what I try. I’ve taken it apart redid the thermal paste. Cleaned the motherboard. Put it back together and still don’t get an image. I’ve tried resetting the video output by holding the power button for the double beeps. Didn’t do anything. Removed the hard drive, just in case that was the problem. Still nothing. Everything on it works fine. Power button is good, it takes and ejects disks normally and I can connect a controller. But no image.

If anyone has some advice or tips that might help me get and image, im all ears. Wondering if anyone has similar problem. Any help appreciated. Thank you in advance!