AMD's Bobcat and Bulldozer

[btarunr]

Here we have the reason. Integrated PCI-Express controller.

EDIT: Well obviously not, but that what techpowerup claims.

There's "L3 Cache and NB" and "Integrated Northbridge Controller".

The "NB" in "L3 Cache and NB" is the northbridge component found on AMD processors since K8. The "Northbridge Controller" is the IOMMU (what we're used to referring to as northbridge, such as AMD 790FX) integrated into the processor die.