What I said was true (although not nice). If someone can afford a 980/980ti they would not put it in a 5 yearold system.
Why not?
A Xeon X5650 can perform as well as a 4790k when all of the threads it has are utilised.
If it works then you can do it. TBH if I still had my X58 board (I'd have been screwed any way I had a Foxconn) then I would get myself a hex core Xeon for absolute peanuts (I've seen them sell for £40) and then simply spend the rest on a GPU.
In gaming it's pretty much all the GPU. Sure, you can't run a gaming rig on a dual core Pentium or Celeron but anything with a few cores and some grunt is usually good enough.
A hex cored Westmere at 4ghz or more is no slouch. Most certainly still fast enough for any single GPU available atm.