I have an old desktop PC which has a P4M900T-M2 motherboard. It currently has one Apacer DDR2-667 memory module but the motherboard can support two DDR2 memory modules. I'm planning to upgrade it to have 2GB of memory (1GBx2).
My question is, do I need to have two identical memory modules?
Or will it work fine if I just install a different one to be paired to the existing one?