Lenovo 3000 J Series - Manual (Page 39)

Locating components
The following illustration will help you locate the various components in your
computer.
1 Microprocessor and heat sink 5 PCI adapter connectors
2 Memory modules 6 PCI adapter
3 PCI Express x1 adapter connector
(some models)
7 Power supply assembly
4 PCI Express x16 graphics adapter
connector (some models)
Identifying parts on the system board
The system board (sometimes called the planar or motherboard) is the main circuit
board in your computer. It provides basic computer functions and supports a
variety of devices that are factory-installed or that you can install later.
Chapter 3. Installing options 21