Each memory slot can hold DDR2 PC2-4200,DDR2 PC2-5300,DDR2 PC2-6400 with a maximum of 2GB kit (1GBx2) per slot.*
Your system requires that you install memory in pairs.
To benefit from the performance advantages offered by dual-channel systems, you should install memory in identical pairs.
Installing a kitted pair is the best way to ensure that your modules are identical, right down to the chip count.
Your system does not support ECC. Because ECC and non-ECC modules should not be mixed within a system, install the same type of modules
that are already in your system.
That info is from crucial.com
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