IGP may be on motherboard or CPU.
Which is exactly the point I was trying to make. "Onboard graphics", as I perceived it, was being used as the generic term for IGP. Likewise, if I called AMD's APU "onboard graphics", or an "IGP", somebody here would likely pitch a fit and say, "duh, AMD doesn't have IGP, they have APUs". So, as someone who is argumentative, but not necessarily overly picky about terminology, a machine with, "onboard graphics", is any turd that will still boot, and doesn't need a separate "AIB", "VGA", or "video card", shoved up its socket to put a display on a monitor.
As to whether or not, "Intel has the best IGP", I think it's a certainty of current opinion that, "anything Intel can do, AMD can do better". (Do remember, I wasn't the one who suggested that).
Any of that notwithstanding, and being the uninformed Luddite I am, I still build with Intel. And it spite of the fact that Intel's IGPs suck, I won't buy an Intel CPU without it. But bear in mind, my newest machine only has to beat my last machine, not anybody else's. I consider a machine, "finished", after I have video output, but before I install a VGA.
Well, that's it for now, ('yay' I hear you say). I'm going off to ruminate on the sociological and psychological implications of the Steam survey. Either that, or maybe I'll just take some of my "sleeping powders" and turn in for the night.