Dell Dimension 3100C - Manual (Page 63)

Removing and Installing Parts
63
NOTE:
Memory purchased from Dell is covered under your computer warranty.
NOTICE:
If you remove your original memory modules from the computer during a memory upgrade, keep them
separate from any new modules that you may have, even if you purchased the new modules from Dell. If possible,
do not
pair an original memory module with a new memory module. Otherwise, your computer may not start
properly.
matched pair of memory
modules in DIMM
connectors 1 and 2
1
2