i have i5 2500k and now using z68 MOBO.. i heard a lot of people said that intel second gen is really compatible with z68's chipset but, i'm really confuse either i need to change the MOBO from z68 to z77 since i have GPU gtx 670 which used pci-e 3.0.. but my z68 have only pci-e 2.0 slot.. i'm worry if my z68 will bottleneck my system.. but at a same time i don't want to waste my money just for the same performance.. i will change the MOBO if you guys tell me to do so.. maybe for the future.. but please help me.. thanks guys..