Haste, Haste Speed Boost, and Jorgundal's Collar

[Quarterling]

So which of these stack with each other? Do they all stack, only some of them, etc?

Haste Speed Boost comes from the Rogue's Enhancement Rogue Haste Boost IV (+30% attack speed for 20 seconds) and the collar makes melee attacks 10% faster than normal.

[Baahb3]

Haste gives a 15% Enhancment bonus to attack speed, the Rogue enhancement is a generic bonus and Jorgundal's Collar gives a 10% Enhancement bonus.

So Haste and Action boost or Collar and Action Boost, but not all 3.

[Yajerman01]

Jargundalls does not stack with haste but haste enhancement lines.

[Quarterling]

Alright, thanks all for the quick replies.