Sounds a bit like a desperate post to try and convince that the MSI is equal to me.
Ooooooo someones tired!
We have no idea when the OP is ordering the kit so it's important he understands the differences should he be looking to buy once this weeks offers expire.
By RRP the Frozr III is cheaper. The Windforce X2 at it's RRP goes head to head with the Frozr IV which isn't voltage locked so in my eyes that is the better 7850 GPU.
OP said he knows very little about overclocking so I have tried to show how easy it is to do and get more bang for his buck. He might well get the Windforce, just because it's technically better "out of the box" doesn't mean that it can't be tweaked aswell and improved from factory settings for both speed and noise. That was the point of me talking him through afterburner.
It's also worth mentioning the LucidMVP software that comes with the Z77 mobo. As it can switch between the IGP and the dedicated GPU depending on what's needed to save power. Infact the IGP can be used to boost the GPU but this is only really making a difference on much more budget orientated GPUs. If it's starting to sound complicated we are always willing to help walk people through the build.
I don't mind which spec he uses honestly. I think Sparx and Idleman did a good job too. As his boy wants a gaming rig then the 7850 makes a lot of sense as it's known as a good OC'er and comes with a nice bundle of games. If his boy does any video encoding or might well want to, he could consider the nvidia 660 for it's CUDA support. Somehow I think he will take the free games over this option but I'll still point it out all the same.