I need some advice with my rig.

[QwertyMusicMan]

Hello all, I would really appreciate some help. I'm inheriting a state-of-the-art gaming rig, which unfortunately doesn't hold-up by today's standards, as it was top of the line in 2006. This computer means a lot to me, so I would rather upgrade it than build a new rig. The case is in great condition and looks awesome, the PSU is 550w or so. Obviously, I would have to replace the mobo, GPU, CPU, and RAM. I'm just wondering how I should go-about doing so.

The computer is outfitted with a water-cooling system, which I'll likely have to remove. I'm not sure if there is also a fan in it. I'm looking to play higher-end games, especially the forthcoming BF3 on higher settings. I want to replace the parts with:

mobo: Newegg.com - GIGABYTE GA-Z68MA-D2H-B3 LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 Micro ATX Intel Motherboard
or
A comparable AM3 mobo, if not i5

CPU: AMD Phenom II X4 965
or
AMD Phenom II X4 955
or
Intel i5 2500k

GPU: GeForce GTX 570
or
GeForce GTX 560

RAM: 6GB or 8GB DDR3

In other words: I need someone to tell me if I can upgrade this computer easily, and if so, which set of parts would be the best cost-to-value ratio for game performance. Thank you so much.

 

[Roark]

In general, AMD is usually king of cost:value for CPUs.
That being said, I believe the 2500k is currently the best gaming CPU.
(Here is some ram for the 2500k)

I'd personally go with a GTX 560Ti, its about $100 less than the 570 and will do just fine with current games.
If you have the money, there is nothing wrong with getting a 570.

There are some things to keep in mind:
1) You might need to purchase a new copy of Windows if you had an OEM version on your last computer.
2) Your optical drives / hard drives may not plug in to the new motherboard. Open your case and see if any of the drives attach to the motherboard with a flat ribbon about 2-3" wide. If so you'll need to upgrade those components as well.

 

[Yami]

In general, AMD is usually king of cost:value for CPUs.
That being said, I believe the 2500k is currently the best gaming CPU.
(Here is some ram for the 2500k)

I'd personally go with a GTX 560Ti, its about $100 less than the 570 and will do just fine with current games.

I have basically that setup, and can recommend it.