Number 1
It's ~3 years old afaik.
It's quite a bit better than number 2.
But it has been OCed, so that is something to keep in mind. (It's been running hot for however many years)
It's better than the other 3900kr computer too.
The thing with second hand pcs, pretty much 0 warranty. If it dies, game over.
Also you would be starting with a 3 year out of date PC. It's a bit like handicapping yourself.
I don't think the 470 has DX11 capabilities, and will probably be lacking other newer features introduced in the last 3 years.
Though if you plan on gaming on medium, it's fine. (Will probably outperform the 650ti too)
Also since it's barely scratching your budget, if it does die, you can always get another
.
PS: I'd still go for the build your own option ;)