The machine you have should be fine. Unless you are trying to get 120 FPS.
I have Win 7 Home Prem 64
SamsungSSD 128 gb
8 GB Ram
500 GB hd
NVidia GeForce GT 640 2GB DDR3
AMD Phenom 9950 QuadCore 2.6 GHz
I know I need upgrades..................................but
What do I need to upgrade? Everything?
Looking to play some latest games like COD Ghosts BF4 and a few others.
"It doesn't take a profound understanding of GPU architectures to guess that DDR3 could needlessly hamstring the GeForce GT 640 compared to its GDDR5-toting rivals. The peak theoretical numbers below lend weight to that notion:"
If you decide to move up to a better card, pick from this list.
http://www.tomshardware.com/reviews/radeon-hd-7770-7750-benchmark,3135-6.html shows some 35ish FPS rates at high detail on BF3 so I'd pull that back to medium detail and be out about 100.
"Our tests demonstrate fairly little difference between a $225 LGA 1155 Core i5-2500K and a $1000 LGA 2011 Core i7-3960X, even when three-way graphics card configurations are involved. It turns out that memory bandwidth and PCIe throughput don't hold back the performance of existing Sandy Bridge-based machines. "
Since you are not going three way, I doubt that's an issue today.
Light bulbs you shouldn't buy
There are plenty of dimmable LED light bulbs, but make sure you don't buy the ones that flicker when you dial them down.