So, my bios revison is 1.15.5 , that, checked on Dell website, it's the last one... I've installed Catalina with this version.
But one thing that i don't remember ( did'nt read back all posts), is if I've already told you abaout DVMT modification in BIOS...for do this I needed to Disable CFG-Lock...I had to do this on my Dell XPS too...
If I've get it's meaning, it will let Mac os to write variables in bios that the os needs for CPU power management and other stuffs... by unlockinbg this, I can set the total ammount of preallocated memory for get osX boot on a larger res display.... maybe I'am confusin my self and everyone else lol...
But
@TomJones, how did you set the bios?
Just a little upgrade: ?ve bought a Wi-Fi PCI-e card that enable continuity and Handoff... afther some weeks, I've installed a R9 Nano .... BOOM!!!! Proud to say that it was awesome!!! But to much HOT!!! lol
Don't give up TommyLeeJones
, I'll try to suport as much as I can