Ram?

[Pikabuddy]

Hi my iMac (mid 2007)has 1GB of ram. I want to upgrade the RAM to 2GB. I've never really had experience with RAM before. So I was wondering, if I bought 1GB of RAM, could I add it to my existing 1GB of RAM or would I have to buy a 2GB RAM slot and replace my 1GB?

[flopticalcube]

Your iMac has one 1GB stick so you can add another stick (of any size).

[Hellhammer]

Your iMac has single 1GB module and one empty slot so you can get up to 5GB without removing the old stick