System upgrade bottleneck NEED HELP!

Hello, I'm new to this forum, and I've been planning to upgrade my rig over the next couple months (maybe pick something up on black friday, cyber monday, or boxing day) and I'd like to know where I should start to improve my PC.

My current build:
8GB DDR3 ram @ 1600 (Cant remember the brand off the top of my head)
Corsair 850W power supply
Some old AM3 motherboard with SATA 1
AMD Phenom II X955 BE @ 3.2 GHz
Nvidia GTX 560
128 GB Crucial M4 SSD (Yes I know I only have SATA 1 so my SSD runs far slower than it could)
Some old shitty 500GB HDD @ 5600 RPM

I mostly game on my machine, but I do occassionally do programming, but I dont use (many if any) heavily threaded applications.
Okay Basically my question for all of you friendly people here is:
If I was planning to upgrade my machine (It's between a new CPU & MOBO, or a new GPU)
What is my current bottleneck? (AKA. which part should I upgrade first AKA NOW)

I was thinking that it would probably be better to pick up a new MOBO with sata 3, and getting a Haswell chip too, and I was looking at:
I5 4670K
and picking up an aftermarket cooler, and OCing it to around 4.2 GHZ, but in the end it would cost ~$120 more than just picking up this:
I5 4570
Which fits into my budget far better, and I'd have more budget towards a GPU.

Or If i was planning to get a R9 290 (Non X) card (AFTER third party cards become availiable as MANY retail cards are unstable ATM from what I hear) and then picking up a cooler for this thing OR a 4 year warranty (so it lasts longer than 3 months, as from what I hear again, they run really hot, and have a high chance of burning out fast)

So to state the actual questions that i'd like answers to:
1) Whats bottlenecking my machine more currently, the Phenom II 955, or the GTX 560? (I was thinking since I've had my processor so long, i may just try and OC it to ~4.0 with the stock fan until it dies, as my case has 5 fans that already keep an extremely cold airflow in the computer) and if I do this, will getting an R9 290 run new games decently with my OC'd 955?

2) If I really need to get a new CPU/MOBO asap, should I go with the 4570 so I can purchase an R9 290 earlier (will this CPU bottleneck the card hard though I wonder??), or should I just go with the 4670K, get a fan, OC it, and wait a while longer for a GPU (Although I'd rather not go down this route, I know that my 560 is in need of an upgrade as well.)

3) ANY alternate help/solution/build is greatly appreciated. That being said, Ive already decided I'm going to shy away from an AMD chip unless a very convincing argument is given.

Thanks a lot guys !