How to play games with cpu instead of gpu*

So I realize this may sound like a bad idea but please hear me out first. I enjoy making things on blender (despite not being very good at it) so I'm almost always rendering stuff with my gpu. There are times when I want to play games while rendering at the same time but I can't because my gpu usage is already at 100%. So I guess my question is, "Can I make it so that games ignore my gpu allowing them to only use my cpu?".

edit: I just realized that "games" is a very broad term as they are not all the same so by games I am referring to Minecraft and osu!.

Even if it were possible, you would have absolutely horrible performance. 

EDIT: You aren't talking about using the integrated graphics on your cpu rather than a dedicated graphics card are you? If so that may be possible though I haven't had integrated graphics in 8 or 9 years so I have no idea how you would do that. 

Yes.. I was referring to using the integrated graphics in my cpu. To be honest I have yet to test the performance difference between cpu rendering and gpu rendering (for my specific rig which has a 4770k and gtx780). I just assumed gpu rendering in blender was faster.

The iGPU in the 4770k *should* be enough for minecraft, but I'm not certain what settings you'll be able to put it on.

No idea if this is a viable thing to do though.

I`ve played vanilla Minecraft with nothing but i3-4130 and it`s integrated Intel HD Graphics at graphics set to fancy, render distance 12 chunks, FOV 80 and resolution being 1080p. Been getting around 30fps with occasional drops when entering large caves. 

Don`t know how about using CPU graphics instead of your GPU though

igpu is fine for MC , I had it running at 60+ fps on the highest settings ( back in 1.8 beta when I had my 3570k with igpu ).

This seems possible , and there is something like this , long story , somebody else will explain .

That makes more sense, I thought you wanted to do graphics processing with the CPU, not the iGPU.

intel HD graphics are more for web browsing and video watching. not gaming. now if intel had a decent APU i'd say otherwise