Here is the Dell website for your 'puter. The documentation says you have to add in pairs of alike size.
http://support.dell.com/support/edocs/systems/dim8200/replace.htm#1101964
I have a question about RIMM Memory. I want to upgrade my memory in my Dell Dimension 8200 I currently have 2 128Mb modules. I want to buy one 256 memory to replace one of the memory modules. My question is do I have to have two of the same or can I mix them i.e one 128 and one 256.

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