Originally Posted by Alatar
But the business side of NV can't make engineering decisions overnight and just decide to release big Maxwell chips on 28nm...
If such designs were to be released the design process would have begun ages ago, way before it was known that 20nm would not be ready yet. Just tape outs would have had to happen nearly a year ago.
Also the reason AMD is losing so badly with perf/watt in the high end is because they clocked their Hawaii cards stupidly high in order to get good reviews. GK110 per/watt flies out of the window once you actually clock it a bit higher. GK110 has 150-200MHz higher clock potential than Hawaii yet the reference GK110 cards are released with lower voltages than AMD designs and in some cases lower frequencies as well. GCN 1.1 efficiency is not that bad if you look at the 7790. Again, don't look at super high clocked "look at me I win at reviews" versions of the chip (260X or with hawaii 290X uber).
Pretty much all of this indeed.
Hawaii's extreme density and poor choice of cooler along with high clocks causing it to need a lot of voltage to attain those high clocks.
It goes a lot better with a good cooler and lower clocks actually some users reporting to have it down to 160 - 180W with some downclocking. Still it's density decreases max clock and increases leakage.
Now we are all out speculating seeing how TSMC is booked to full capacity and not by Nv or AMD. I myself think GloFo will get a piece of the cake actually I know they will. AMD's latest agreement with GloFo for their continued "partnership" AMD's CEO Rory Read stated GloFo would produce chips for the game consoles and gpus. (obviously he doesn't want more penalties since than 200m penalty they got a couple of months ago could've been forseen if the chips went there to begin with. (they were too late to do that probably and optimized for TSMC)
Anyhow I think both Nv and AMD will shift towards GloFo for 20nm if TSMC can't provide.
As for Maxwell the iniatial performance and performance/watt numbers are very good. And all with increasing cache a bit or is there a far deeper secret that yields most of these gains?! Either I deduct intel from AMD's claims for mobile about the new GCN version (pirate islands if I'm not mistaken) they cut their TDP/SDP in half with Mullins versus Temash considering it is pretty much on the same 28nm that means they halved the power consumption. Most of the SoC's power with Temash was coming of the gpu so they made huge gains there. (I know this because notebookcheck's review states Cinebench loads all cores yet doesn't show big consumption compared to a graphics load)
I sincerly doubt they can scale it up but it is an indication that Pirate islands may come very close to Maxwell as Mullins versus Temash halves power and increases gpu perf by 20%.Edited by maarten12100 - 4/6/14 at 3:46pm