head-splitter :
REGULATOR2K :
After thinking on this some more my only concern for your current system would be the amount of RAM on your GFX card, this could turn into a bottle neck for you, it it were me, i would wait until that bottle neck arises then take action.
Yeah, RAM doesn't worry too much since it's cheap and so easy to replace. What concerned me more was if I had to switch out my entire CPU and GPU (at which point I might as well change the motherboard too). I still don't understand that much about multithreading, so I was wondering if the PS4's 8-core processor would at some point outperform the x4 965's quad cores.
That, and like Madn3ss795 said, the ps4's GPU is supposed to be on par with the HD7850, which according to GPU benchmark outperforms the GTX460 SE.
It's possable that in a 2-3 years time the 8 core might be better optmized for gaming than your x4 965 but i doubt it, the reason being is that the PC desk top world has been living in a multi traded world for 6-8 years now and most games only use two CPU CORES at most, what is more important is the raw performace potental of the processor in use.
In terms of performing like a 7870, a mobile one,yes, a desktop 7870? no chance, it just does not have enough wattage to give the performace of a desk top part, this is internet spin working at its best to sell a new product IMO.(search on TOM'S for reviews of AMD'S current mobile and desktop APU reviews and you will get a good idea of the massive step back these systems are to your current dedicated Desktop build)
If you can think of it as in terms of buying a new car, the PS4 like a good family salon with the PC CPU you have being like a base model sports car......they are both cars but both in very different markets.(GPU as Well)
My point on GFX card Ram regards that what we have seen from current games being released are starting to use up more and more video RAM, we are getting to a point were 512-1gig of onboard ram may not be enough to be able to turn all GFX options.
Any ways, I hope all this helps you somehow and I hope i do not come across as being anti PS4 or any thing like that (I think consoles are great for gamers on every platform) i just would not want you to spend money on something that your current system is better than.