Dell OptiPlex 330 (Late 2007) - Manual (Page 76)

Inside View of Your Computer
System Board Components
CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.
CAUTION: To avoid electrical shock, laceration by moving fan blades, or other unexpected injuries, always unplug your computer from the
electrical outlet before removing the computer cover.
NOTICE: Be careful when opening the computer cover to ensure that you do not accidentally disconnect cables from the system board.
1 drives bay (CD/DVD, floppy, and hard drive) 2 power supply
3 system board 4 card slots
5 heat sink assembly 6 front I/O panel
1 internal speaker connector
(INT_SPKR) 2 processor connector (CPU)
3 processor power connector 4 memory module connectors