Steps to upgrading my computer overtime- Starting with cyber monday!

[timoteo]

So my current computer is getting a little dated and its time to upgrade a bit. I have decided that on black Friday/ cyber Monday I am going to try and upgrade
1: The hard drive to a 1tb(obviously this will include a new OS)
2: The Mother board.
What I am looking for is suggestions on what to get, namely in the motherboard portion, as well as any insight if this is a plan that will work.

My Cpu consist of
intel Core i3 2120 3.3 ghz processor(would like to upgrade to an amd processor
500 watt power supply,
AMD Radeon HD 6670 graphics card,
8 gb of ram.
500gb hard drive.
The plan is to upgrade the motherboard and harddrive now and then upgrade the processor to a quad core amd along with adding 16gb of ram.
And finally getting a $200+ graphics card to finish it off.
obviously my build is a midrange build and the prices should reflect that, but overall the cost of the Hard Drive and MB are adjustable.

[chazus]

A few things...

1) You can't upgrade 'just' the motherboard without the CPU, unless you plan to just let the board collect dust until you get the CPU, which seems silly.
2) 'Upgrading' to an AMD is a downgrade, more or less. If you plan on upgrading, then get a newer Intel and board.
3) What do you need 16gb ram for?
4) What is your budget range and playing desires?