I doubt it would be too much of an issue. if his PC meets the rest of the requirements it's sure to have at least a 300W psu. and I'm sure there are low end cards that will run the game that require less than 300w.
I doubt it matters anyways though. I kind of get the impression he's either using a laptop or a PC that is either a very low end wal-mart pc, or something that is very old. I think it's unlikely he has a pc with a quad core processor, 6 gigs of ram, but running on integrated graphics.
Well the Intel HD3000 he has comes with the Intel Sandy-Bridge processors, so if he has a desktop with an i5/i7 processor he can pair that up with a powerful GPU and be all good.
If he has a laptop though then yeah there's nothing he can do.
But if he has a desktop with a i5/i7 processor though, why would he waste money buying a low end card? there's no point. Why would you buy something that already struggles to play modern games today, you're just wasting money. Ontop of that it would be a serious bottleneck to his processor. If this guy is really into PC gaming, and wants to get something out of his purchase, he will need to get something decent, and decent video cards like a GTX560 for example will require atleast a 500w PSU minimum.
But yeah point is, if you're going to pay for something, make sure its worth it. There's just no point in buying something already pretty much outdated , struggling to do its job. Alot of people make the mistake of doing that thinking they will save more money when they actually will spend more because they would need to upgrade in a shorter period of time as the parts they bought already struggle. If you buy something that's decent however, you wont have to upgrade for awhile, so you save more money basically.