AMD+ Quad Core Help. It's a matter of 60 bucks.?

I have an AMD x2 3800 2.0 Ghz processor right now, and am about to upgrade to quadcore. However, I need some help. I could buy the AMD Phenom 9650 2.3GHz 4 x 512KB L2 Cache 2MB L3 Cache Socket AM2+ 95W Quad-Core Processor, which is $119.00 or I could buy the AMD Phenom II X4 940 Deneb 3.0GHz Socket AM2+ 125W Quad-Core Black Edition Processor which is $189. This upgrade will no matter what include the ECS BLACK SERIES GF8200A (V1.0) AM2+/AM2 NVIDIA GeForce 8200 HDMI ATX AMD Motherboard, and OCZ Reaper HPC 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory. That means a new faster mobo, and DDR2 1066 RAM, while I now only have 2GB of lame-*** RAM. I also have a GeForce 9600 GT, and if I get the cheaper one, then I might get another card and run SLI. This means that no matter which CPU I pick, it'll be faster than what I have. What I want to know is, how much faster will it be? I mean, if I buy the cheaper one, will it be leaps faster than what I have? Or will it take the more expensive one to notice a difference. I play PC games like Crysis, M Effect, and GTA, so I need something fast, but I don't want to have to pay for a lot more if I don't need to. Thanks.