I would not use that power supply, it's pretty bad. If you only want to run a single GTX560 Ti then you only need 500-550 watts from a good power supply manufacturer. If you plan on adding another later in Sli you would need a good 750w unit. Stick with Corsair, Seasonic, PC Power and Cooling, XFX, Antec, Enermax or Silverstone. Here is a pretty good guide to go by.http://www.eggxpert.com/forums/thread/323050.aspx
If you are going to overclock you need a CPU cooler. The Coolermaster Hyper 212+ and Hyper 212 Evo are both good low cost options.
Do NOT use that RAM for a 2500K. You need 1.5v RAM or you will void the CPU warranty. I recommend GSkill Ripjaws X or Corsair Vengeance.http://www.newegg.com/Product/Product.aspx?Item=N82E16820231428http://www.newegg.com/Product/Product.aspx?Item=N82E16820233196
Either of these kits will fit under an aftermarket CPU cooler.