Thank you for writing to us.
Below is the supported configuration in memory for XPS 8300:
Memory module Connectors: Four user-accessible connectors
Memory module capacities: 1 GB, 2 GB, and 4 GB
Memory type: 1333 MHz DDR3 nonECC memory only
Minimum memory: 3 GB
Maximum memory: 16 GB
Possible memory configurations: 3 GB, 4 GB, 6 GB, 8 GB, 12 GB, and 16 GB
You can access this information by checking on the user manual for the XPS 8300 system on our Dell Support site by entering the system service tag (which will retrieve the manual, drives and all other related information regarding your system).
Hope this helps.
Kindest Regards ,
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