Fixing slow (2+ minute) boot times on new AM5 builds (Memory Context Restore & Power Down Enable)

I see this question like 5 times a day here. Someone builds a sick new Ryzen rig, turns it on, and sits there staring at a black screen with the yellow/orange DRAM debug light on for what feels like eternity.

Don't panic. You didn't break anything. It's just DDR5 doing memory training every single time you turn it on.

To fix it so your PC actually boots in 15 seconds like a modern computer should:

1. Go into your BIOS.
2. Turn on EXPO for your RAM (obviously).
3. Search for a setting called "Memory Context Restore" (usually under DRAM timings or Overclocking menus).
4. Enable it.
5. Crucial step: Also find and enable "Power Down Enable" (if you leave this on Auto/Disabled while MCR is on, you might get random blue screens).

Save and exit. Your very next boot will still be slow because it has to train one last time, but every boot after that will be lightning fast.

Save yourself the headache.