((Lower DMG + Upper DMG) / 2) / WeaponSpeed
[Dragonstrike]
((184+343)/2)/2,7 = 97,592592
and now with +4 weapon damage
((184+4+343+4)/2)/2,7 = 99,0740740
1,48dps gain
Yup some rounding errors upps, see 2 posts above for corrected numbers.
Regarding haste, it does not really change anything because lets take Dragonstrike again and we put the above formula into the equation then assume haveing eg: 135 Haste Rating (Haste Rating: 10.5 rating grants 1% haste ) 12,85% Haste.
You have the Haste with or without the ring enchants.
I took this 135 Haste Rating number from
The Sunwell Fury Warrior - Gear Choices @ 25.04.2008 - 03:34 | Nihilum.eu - MMORPG Gaming Guild and Community
Lets say we dont have a + weapon damage ring enchant now. The speed from the Dragonstrike would be 0.347 faster so WeaponSpeed = 2.35
((184+343)/2)/2,35 = 112,1276dps
and with +4 weapon ring
((184+4+343+4)/2)/2,35 = 113,829dps
1.70dps gain or ~ plus 0.2 compared to 0% Haste versus 12,85% Haste