Terminology

• The processor to I/O controller is known more commonly as the "southbridge," according to the website Directron. It makes up half of the motherboard's "chipset." The other half is the "northbridge," which allows for communication between the processor, video card and memory. In Intel chipsets, the southbridge is called the I/O controller hub (ICH).
  
  

Function

• Generally, the southbridge does not communicate directly with the processor. Rather, the northbridge connects the two. This is partially because the devices the southbridge controls are less critical than those associated with the northbridge, and thus do not require the fastest possible access to the processor.
  
  

Identification

• According to the website Computer Hope, the southbridge is smaller than the northbridge. It also is located farther away from the processor. The processor and northbridge often contain heatsinks and cooling fans. While these also may be present on the southbridge, they are noticeably smaller.