Equivalence Dell, HP and IBM

Here is some equivalence spec with different brand:

Dell EqualLogic storage

--> HP P4000 (LeftHand)

--> IBM: none available

Dell PowerVault MD storage

--> HP P2000

--> IBM DS3500

Dell PowerEdge R720 server

--> HP Proliant DL380p G8

--> IBM x3650 M4