Upgrading MOBO for a new GPU?

manyhighfives

Honorable
Feb 9, 2014
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10,510
Greetings! Here's what I have goin for me:

GPU: Nvidia GTX 560 Ti
CPU: Intel i7-2600K 3.40 GHz
MOBO: ASUS P8Z68-V LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 ATX
RAM: 12 GB
PSU: 675W

Question: I first build my rig a couple years ago, and I want to update to a GTX 600 series, potentially, and I was wondering if I need to upgrade anything else. I'm a bit of a novice when it comes to understanding PCI express 3.0 x16 (which most of the GPU's on the market advertise) as compared to PCI express 2.0 x16 (which I have). What do?