you're better off not investing in a Z77 motherboard and save yourself a few bucks by getting a H77 motherboard instead. you're not going to overclock either way.
Newegg.com - ASRock H77 Pro4/MVP LGA 1155 Intel H77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
depending on where you live, you can save a little more money ordering some parts elsewhere.
Intel Core BX80637I53470 i5-3470 Processor - Quad Core, 3.2GHz, 6M Cache, SSE4.1, Core i5, LGA 1155 at TigerDirect.com
Corsair CMZ8GX3M1A1600C10 Vengeance Desktop Memory Module - 8GB, PC3-12800, DDR3-1600MHz, 240-pin DIMM, 1.5V, CL10, Intel XMP Ready, Unbuffered at TigerDirect.com
there's sure to be sales and combos lurking around if you're more vigilant than i am