Acer V12LC User Manual page 4

1.1.2 Slot Board
The system board comes with a slot board already installed. The slot
board carries the PCI and ISA bus slots for system enhancements and
future expansion.
The slot board may vary in size and layout depending on your system
housing. Figures 1-2 to 1-5 show the four kinds of slot boards.
Figure 1-2 2-PCI/3-ISA Slot Board (for generic desktop systems)
Figure 1-3 2-PCI/3-ISA Slot Board (for Aspire desktop systems)
1-4 User's Guide