1. If you only loot ammo from bodies, you are cutting your ammo haul in half. Picking up an enemy's gun gives you the rounds it held. Be sure to stuff all the useless guns in the last dead guy so they disappear from the world and don't bloat your save file.

2. The usefulness of Damage Resistance decreases exponentially. DR of 1000 is only a little bit better than damage resistance of 200. Details here https://fallout.fandom.com/wiki/Damage_Resistance

3. DR is not per limb. Adding DR to a limb protects your whole body.

4. Armor perks are not per limb, i.e. adding Dense to your arm protects your whole body.

5. The attributes of armor you wear don't count when inside power armor, even when the corresponding power armor piece is blown off - but the exposed limb is still protected by tip number three.

6. Every Agility point reduces reload speed about 5%.

7. The Assassin's (armor attribute) 15% damage reduction from humans doesn't seem like much, until you stack 5 of them.

8. The armor modifications Dense and Padded don't stack with themselves, but do stack with each other. Cushioned does stack with itself. More on fall protection stacking:

The formula seems to be fall damage = Raw fall damage * { (1-(0.5*[num freefall legs])) * (1-(0.5*[num acrobat legs])) * (1-(0.25*[num cushioned legs])) }

1 Acrobat (or Freefall) and 1 Cushion gives 38% damage
1 Acrobat (or FreeFall) and 2 Cushion gives 25% damage
1 Acrobat, 1 FreeFall and 0 cushion gives 25% damage
1 Acrobat, 1 FreeFall and 1 cushion gives 19% damage
1 Acrobat, 1 FreeFall and 2 cushion gives 13% damage
2 Acrobat or 2 Freefall give 0% damage.

9. Running in power armor moves you twice a fast, but uses fusion cores four times as fast.

==== these next tips feel like cheating ==========
10. When you command your companion to pick something off the ground, the weight check is skipped. You can have them haul unlimited stuff around this way.

11. If you have your gun out and tell your companion to go somewhere, you get a free weapon laser pointer.

12. There's a Strong Back perk that normally allows fast travel while over-encumbered, but In Survival mode (which has no fast travel), it changes to no leg damage when over-encumbered. With the other Strong Back perks and a little action point buffing you can carry unlimited weight easily in survival mode.

13. Explosive and wounding legendary effects on a shotgun are per pellet, which is OP. No enemy in the game has resistance to Wounding's bleeding damage (which stack per bullet), not even robots. On a lowly .38 automatic, Wounding and Kneecapper can vanquish the biggest enemies quickly.

14. A Nimble Legendary weapon will move you 1.75 times as fast as walking when the weapon (must be un-scoped) is higher than your navel. You can zip around in power armor without the fusion core drain of running. You must reload or sprint every time you equip the Nimble weapon for the effect to start working.

==== Very non-obvious: How to move a dead body ====
Get out of your power armor. Place your right hand in contact with the body, note the loot menu appears. Lift your pipboy slowly towards your face until the loot menu on right hand disappears. Click and hold the center of right thumbpad (or A button if you don't have wands) to pick up. Release to drop. If it keeps respawning, walk it to another cell and drop it there.

==== Non-Obvious Performance tip ====
Turn on your XMP in BIOS. While most games get almost no benefit from running RAM faster, Fallout 4 is the exception. XMP won't run your RAM faster than your motherboard and RAM manufacturer recommend.

Stability tips: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3082227285