| Baron said: An 8 core mobile cpu and supposedly a 7850 with 4 GB's of RAM which I find very doubtful, a graphics chipset of at least 130 Watts paired with a processor that will most likely use about 1/10th of that... |
Mobile GPUs have special binning process (i.e., they can achieve similar clock speeds at much lower voltages or can drop clock speeds a little bit with a very large reduction in voltage). For example:
HD7870 Desktop (1000mhz, 1280 SPs, 32 ROPs, 80 TMUs, 256-bit bus, 153.6 GB/sec memory bandwidth, 2GB GDDR5) = 175W TDP
vs.
HD7970M (850mhz, 1280 SPs, 32 ROPs, 80 TMUs, 256-bit bus, 153.6 GB/sec memory bandwidth, 2GB GDDR5) = 100W TDP
^ 150mhz lower GPU clock and a 75W reduction in TDP.
http://www.notebookcheck.net/Review-GeForce-GTX-680M-vs-Radeon-HD-7970M.77110.0.html
Since HD7970M launched, the 28nm node has matured. By the time PS4 launches, they could release a similar card with an even lower power consumption since 28nm node will be on 2nd or 3rd stepping.
| Baron said: As for the speed of the RAM. GDDR5 doesn't automatically mean it's extremely fast. There are things like clock speeds and bus sizes to consider. There are graphics cards with GDDR5 RAM doing 25.6 GB/s and there are graphics cards with (simple) DDR3 RAM doing 64 GB/s. |
That is true. People were discussing the specs of PS4 in the context of GDDR5 and memory bandwidth in the vicinity of 176 GB/sec or similar. These specs went hand-in-hand. This is why the talk started that PS4's GPU would mop the floor with the Xbox 720's based on these specs.
| Baron said: I'm expecting something in the range of 7850M - 7870M for both consoles. Enough to run new, next-gen games close to 1080p at (a steady) 30 fps but nothing too fancy. Certainly not enough to match (current) High end PC's right off the bat at launch. |
HD7850-7870 level would be very good for next gen consoles. Earlier rumors from last year discussed HD6670/7670 or 7660D A10-5800K APU. All of those are very weak. HD7850-7870 would be 8-10x the power of PS3's GPU.
Even the GPUs in PS3 was already more than 2x slower than G80 (8800GTX). PS3 and 8800GTX launched days apart. PS3 cost $800+ to manufacture...
Nvidia's upcoming Titan will have 6GB of GDDR5, 235W TDP and cost $900. It's impossible to even consider a console having those, not to mention just how massive these GPUs are! You can't fit that inside a small console :)
