Okay, My current gameserver (hosting minecraft on an old box distro not important because each one does not survive the night so I am thinking its hardware failure) I am going to use Debian when I get it up, as I am familiar with it because I have been using Mint. Installed Ubuntu Server upon a few recommendations and it works very well so far so its going to be Debian or Ubuntu Server... Either way, that is irrelevant, just wanted to give background.

I was talking to my roommate about building a new server and this came up... RAM, and CPU, what is more important? Should I go with a dual core and save money or will I notice issues and should just spend the extra 50 for a quad core. Also, RAM, am I going to notice a difference between DDR2 and DDR3, it is strictly a game server. I host a Minecraft server on it currently and possibly plan on having it stream video, but this may not be needed as my main computer has an i7 and is going to be much better at encoding. I don't have a ton of money (mostly because I have not really wanted to do this upgrade, but the computer does not survive overnight and i do not know why!)

Any feedback is appreciated as I have never hosted a gameserver before this so I do not know what specs are the important ones, thank you all very very much in advance!

None of that is going to matter for a game server, much less a Minecraft server. You'll never know the difference between DDR2 vs DDR3 and I doubt the Minecraft server-side is even SMP aware so it won't matter how many cores you have.

I completely forgot I left this out. My friends and I are interested in running a NWN2 server (It has been done successfully in wine from what I've heard) so I guess thats where the hardware is involved. Not only that its not like Minecraft is the only thing that will come along that we will play. I am just wondering in ANY game server if RAM speed is going to be an issue or if its just good to have quantity for server applications. I realize it may be better to go quad core for future games that may come along that we want to run a server for. All feedback is appreciated.