That depends on the details of the current configuration. Say, the motherboard supports a maximum of 4 GB RAM. Than you can add RAM if you currently have 1 GB. But you can't if you currently already have 4 GB installed.
Let's start simple:
1. You tell more details about the hardware currently present.
2. You tell how old the machine is and what OS it runs.
3. You tell why you want to upgrade.
4. You tell your budget.
Kees
i have an acer 5600 all in one and was wondering what i can upgrade

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