A method includes bonding a first package component and a second package component to an interposer. The first package component includes a core device die, and the second package component includes a memory die. An Independent Passive Device (IPD) die is bonded directly to the interposer. The IPD die is electrically connected to the first package component through a first conductive path in the interposer. A package substrate is bonded to the interposer die. The package substrate is on an opposing side of the interposer than the first package component and the second package component.