It wards for 298 regardless of what gear you have (the base.). I put on all my gear and it is 298, I take off all my gear and its 298. However, it should be effected by 149 (half the skills base is.) Ability Mod, making it 447, then it should be upgraded again by your potency, every other healing and warding ability in the game words like this, except ward of rage. 447 + Whatever your Potency is.