Let's step back and look at some facts the 7950/7970 is 4 year old tech.
4 year old tech vs 2 year old tech or the respun 300 series. Generally an 1100mhz 7950 would equate to the 280x in those guru3d results.
You are quoting 800mhz 7950 results, secondly the r9 290 drivers are older than the 390. Like I said I used a 1175/1600 7950 and I know how it compares to a 290 clocked or stock with the parity 390 wonder drivers, even a 1200 or 1300mhz 7950 will scale another 8 fps over the stock 280x results in the guru3d. I'm not saying the gains aren't there, in some games it's a good jump but most of that gain came from the recent drivers. I'm saying if you've left it to this late to only jump on a 390 then you are kidding yourself it's value for money, because essentially it's not if you look at the timeline of 4 years of progression.
The fact is in over a year you are still paying the same price as the 290's were when they bottomed out for a long time. You are only looking at fps you aren't comparing the whole features of the card to Maxwell.
The 8gb of memory is only viable if you are in cf and there was an r9 290x 8gb anyway. The uvd 4 engine is so outdated that it can't decode 4k video playback, Tonga can with uvd 5.2.
Like I said if all you care about is fps then fine, but don't refuse the facts I bring to the table just because they don't suit your agenda.
As I said in my first post,
They were good cards 2 years ago in the form of the 290's but they are showing their age if you look beyond the fps, they do an ok job but the 300 series needed the die shrink and they would have been amazing.
Why are you trying to make the jump from the 2 cards seem less impressive than it is? Does a 390x not overclock too?
And I'm sorry but a 7950 cannot be compared with a 280x. Its not even close to 280x performance.