Hi gauvain,
Thank you for visiting Sony Community!
There are certain parts that we do not recommend upgrading like HHD to SSD for storage media and Wireless LAN. However, you can always upgrade the RAM, just make sure to check the maximum memory your computer can handle.
For further assistance, we kindly recommend visiting our Sony Global Website for information on contacting the Sony Support Center in your region at http://www.sony.net/SonyInfo/Support/.
Regards,
Vincent
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