PS3 (CHCHE01) - 4USB - Not playing Disk PS2 Games

I am the original owner of this PS3. It’s still working like a champ.
Still play every so often disk PS3 games and some digital ones.

I played some PS2 games in the past. However now it wont play them anymore.
It does read them accurately meaning that it knows when its a (silver or gold) blueray/dvd format?
But when I go to open it the screen just goes and stays on black. Which makes me to have shutdown PS3.
PS3 does play PS1 Games without any problems.

I have changed the hard drive… could that have “messed up” the reading process?
Only other thing I have done was took it apart, cleaned it and replaced the thermal paste compound.

Any ideas how to fix? Please help point in the right direction. Thank you.