You might also be forgiven for assuming that it refers to a core piece of a program.
Neither of those is accurate, though.
The core logic is a term that refers to motherboard chipsets.
The term appears to have fallen out of use when the northbridge was integrated into CPU dies.
This was in the mid-2000s.
There isnt any concrete documentation on why chipsets were referred to as core logic or why they stopped.
One potential reason is that early motherboards had various integrated circuits providing functionality.
They also provide connectivity for other logic processors, such as GPUs.
What Do the Northbridge and Southbridge Do?
The northbridge is directly connected to the CPU.
It provides connectivity to RAM and other high-speed transport buses such as AGP or PCIe.
The southbridge is connected to the northbridge and provides lower-speed connectivity such as SATA and USB.
The northbridge was primarily designed for high-speed data transmissions.
As such, it had an outsize influence on the computers overall performance.
A high-end CPU could often be hamstrung by a low-end chipset providing sub-optimal RAM bandwidth.
Likewise, the gaming performance of a high-end GPU could be limited by poor connectivity.
With southbridge providing support for slower transmission busses, it can be easy to consider it unimportant.
In reality, though, it determines what peripherals are supported.
A cheap southbridge might skip the latest USB standard limiting bandwidth in a way that negatively affects your experience.
Modern Motherboards
Of course, neither the northbridge nor the southbridge exists now in modern hardware.
The CPU itself relatively quickly absorbed northbridges functionality in the 2000s.
This integration resulted in an instant performance boost, especially for the RAM speeds.
It is now connected to the CPU directly.
It still manages much of the lower-speed connectivity on the motherboard.
Some of that, however, is being integrated into CPUs.
Some relatively recent CPU models include USB connectivity directly from the CPU, skipping the chipset.
Once again, its unclear exactly why this is the case.
It may be because of the different brand names for computer chipsets.
Conclusion
The core logic is a term that refers to motherboard chipsets.
Specifically, the term was used about chipsets featuring a distinct northbridge and southbridge.
