Use a 512 KByte RAM Expansion. Recommended for running GEOS. Only a few other programs can use the RAM Expansion.
Hint: Press the Option key to make your changes apply to all C64 windows.

Use a 256 KByte RAM Expansion. Recommended for running GEOS. Only a few other programs can use the RAM Expansion.
Hint: Press the Option key to make your changes apply to all C64 windows.

Use a 128 KByte RAM Expansion. Recommended for running GEOS. Only a few other programs can use the RAM Expansion.
Hint: Press the Option key to make your changes apply to all C64 windows.

Use no RAM Expansion. Almost all C64 programs run best in this mode.
Hint: Press the Option key to make your changes apply to all C64 windows.