Sony PCG-GR300K - Manual (Page 109)

Typical expansion memory configuration
Models with 256 MB memory 1
Total System Memory
(MB)
Slot 1
(MB) Slot 2
(MB)
256 256
384 256 128
512 256 256
1 T he 3 8 4 M B and 5 1 2 M B memory c onfigurations may require the removal and replac ement of original fac tory-ins talled memory modules .
Page 109