Artifacts (head, body, boots) gives you different rune words with different rune power.
Based on your combinations you will get some bonus with value based on total rune power you have.
Agility (LOO-NAH-TEM)
Bonus value per runepower: 6.67
Max value: 500
Intellect (WII-ZER-TEM)
Bonus value per runepower: 6.67
Max value: 500
Armor (WII-TAL-TEM)
Bonus value per runepower: 0.67
Max value: 50
Spell Resistance (capped at 50) (WII-TAL-TIC)
Bonus value per runepower: 0.67
Max value: 50
Strength (FAH-TAL-TEM)
Bonus value per runepower: 6.67
Max value: 500
Attack Damage (FAH-NAH-TIC)
Bonus value per runepower: 13.33
Max value: 1000
Spellpower (FAH-ZER-TEM)
Bonus value per runepower: 10
Max value: 750
Rank(s) of Shadow Demon Path: CRUEL TASKMASTER (FAH-TAL-KIL)
Bonus value per runepower: 0.08
Max value: 6
Rank(s) of Moonlight Tiger Path: RAIN OF STARS (LOO-NAH-KIL)
Bonus value per runepower: 0.05
Max value: 4
Rank(s) of Ancient Dragon Path: ICE STORM (WII-NAH-KIL)
Bonus value per runepower: 0.08
Max value: 6
Rank(s) of Blood Wolf Path: BLOOD WOLF (LOO-ZER-TEM)
Bonus value per runepower: 0.07
Max value: 5
Rank(s) of Moonlight Tiger Path: FULL MOON (FAH-TAL-TIC)
Bonus value per runepower: 0.09
Max value: 7
Rank(s) of Iron Grizzly Path: STORM HARPY (WII-ZER-TIC)
Bonus value per runepower: 0.05
Max value: 4
Rank(s) of Blood Wolf Path: WOLF RAGE (LOO-NAH-TIC)
Bonus value per runepower: 0.07
Max value: 5
Rank(s) of Iron Grizzly Path: STEADINESS (WII-TAL-KIL)
Bonus value per runepower: 0.07
Max value: 5
Strength and Agility (LOO-TAL-TEM)
Bonus value per runepower: 4.67
Max value: 350
Rank(s) of Ancient Dragon Path: FOCUSSED MIND (WII-NAH-TIC)
Bonus value per runepower: 0.08
Max value: 6
% increased non-Mana Resource Generation (LOO-TAL-TIC)
Bonus value per runepower: 0.33
Max value: 25
% increased Ability Damage (WII-ZER-KIL)
Bonus value per runepower: 0.27
Max value: 20
Rank(s) of Moonlight Tiger Path: WINDFURY (FAH-ZER-KIL)
Bonus value per runepower: 0.05
Max value: 4
Rank(s) of Ancient Dragon Path: DRAGON'S BREATH (FAH-ZER-TI)
Bonus value per runepower: 0.07
Max value: 5
Rank(s) of Path: Genesis (FAH-NAH-TEM)
Bonus value per runepower: 0.05
Max value: 4
Rank(s) of Path: Frostmourne and Frostwyrm's Fury (WII-NAH-TEM)
Bonus value per runepower: 0.07
Max value: 5
Rank(s) of Iron Grizzly Path: FLESH WOUNDS (FAH-NAH-KIL)
Bonus value per runepower: 0.09
Max value: 7
% increased Ability Damage for your 4th Ability (LOO-TAL-KIL)
Bonus value per runepower: 0.8
Max value: 60
Rank(s) of Iron Grizzly Path: COLOSSAL STRIKES (LOO-ZER-TIC)
Bonus value per runepower: 0.07
Max value: 5
% increased Ability Damage for your 1st and 2nd Ability (LOO-ZER-KIL)
Bonus value per runepower: 0.27
Max value: 20
Rank(s) of Path: Unholy Aura (WII-ROH-TEM)
Bonus value per runepower: 0.07
Max value: 5
Rank(s) of Path: Storm Claws (FAH-ROH-TEM)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Deathwing (LOO-ROH-TEM)
Bonus value per runepower: 0.05
Max value: 4
Rank(s) of Path: EpidemiŃ (WII-ROH-KIL)
Bonus value per runepower: 0.08
Max value: 6
Rank(s) of Path: Crowfall (FAH-ROH-KIL)
Bonus value per runepower: 0.07
Max value: 5
Rank(s) of Path: The Stars Aligned (LOO-ROH-KIL)
Bonus value per runepower: 0.07
Max value: 5
Rank(s) of Path: Rise of the Phoenix (WII-ROH-TIC)
Bonus value per runepower: 0.08
Max value: 6
Rank(s) of Path: Bull Rush (FAH-ROH-TIC)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Steel Mammoth (LOO-ROH-TIC)
Bonus value per runepower: 0.05
Max value: 4
Rank(s) of Path: Dark Initiation (SIN-ROH-TEM)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Deadly Arsenal (SIN-TAL-TEM)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Ambush (SIN-NAH-TEM)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Phantom Shade (SIN-ZER-TEM)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Elusiveness (SIN-ROH-KIL)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Cold Blood (SIN-TAL-KIL)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Killing Spree (SIN-NAH-KIL)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Executioner (SIN-ZER-KIL)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Rogue Resistance (SIN-ROH-TIC)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Dual Wielding (SIN-TAL-TIC)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Weapon Mastery (SIN-NAH-TIC)
Bonus value per runepower: 0.04
Max value: 3
Rank(s) of Path: Trickster (SIN-ZER-TIC)
Bonus value per runepower: 0.04
Max value: 3
Based on Season 10 version.