PC build-need help for final parts

thank you for finding me the psu and ram they are as good as i wanted them to be and the motherboards are awesome too, but i have a quick question on the mobo, because the the Asrock mobos seem good but people have many problems with it so that scares me a little and i cant get refunds on the msi mobo and then gigabyte has expensive mobos(I want one for $150 or less) the page you sent of the mobos are good, it seems a mmajority have the peripherals i need so if you or anyone else that can help me on the will be greatly appreciated.
And also what is the difference between the core i5 4570 and the 4670k if one is significally better for just a little more money i would like to know.
and one last thing, i typed in my graphics card on google(gtx 760) and i see one by Asus and one by EVGA what is the difference?

Cpu.....stay with the 4570.

Video card......gtx 760 refers to the gpu chip.
Then different makers take that chip and build a video card.
Each maker has their own features.
Sometimes important but often marketing hype.

Mobo.....your on your own.
Narrow it down by the features you want and your budget.
Read the reviews.....do your homework.

For my i5 4570 i have been reading other temperatures people have been getting for the cpu ranging from 40c to ~75c
i dont want to overclock or anything and is the stock cooler it comes with going to be fine enough
i want to play recent and some future games like BF4 am i going to have worrisome cpu temps?
i also want to get some 120mm fans for the airflow and recommendations would be appreciated
thanks for the help

"Our tests demonstrate fairly little difference between a $225 LGA 1155 Core i5-2500K and a $1000 LGA 2011 Core i7-3960X, even when three-way graphics card configurations are involved. It turns out that memory bandwidth and PCIe throughput don't hold back the performance of existing Sandy Bridge-based machines. "
http://www.tomshardware.com/reviews/gaming-cpu-review-overclock,3106-4.html

1. The GPU.
2. A good amount of RAM. For now, today that looks to be 8 or preferably 16GB RAM. I can't write it's the SSD that would help here.

Here's where I choose my GPU (link to follow)
Bob

-> http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107.html

Start with the stock cooler and fans......test.

If the cpu temps are above your liking...some options.

Change the cooler....$$$$
Add fans....noisy and $$$$
Remove the side panel....cheap