Hello, I dont understand the reasoning behing your question if its pertaining to computer motherboards, but I will try to clarify a few things for you.
From Wikipedia(For the sake of me not having to explain):
Based on Intel Pentium-class microprocessors, the term chipset often refers to a specific pair of chips on the motherboard: the northbridge and the southbridge. The northbridge links the CPU to very high-speed devices, especially main memory and graphics controllers, and the southbridge connects to lower-speed peripheral buses (such as PCI or ISA). In many modern chipsets, the southbridge actually contains some on-chip integrated peripherals, such as Ethernet, USB, and audio devices.
Now the chipset doesnt determin the "size" of anything really, all of them are placed on motherboards that are built to a set of standard sizes. As shown here, the most common you'll find in a consumer computer:
If you want more information on Motherboard sizes, look here:Computer form factors Check the chart to the right side of the page.