Hello, you let me curious, how do you have such confidence about Wii U power? you think how much better it will be over current gen? I mean, i also think that the Wii U will be better than Wii in the respective generation, but i don't know how it will be against the new consoles
Over current gen? Not a whole lot compared to typical leaps, around 2-3x overall. Typical performance leaps are around 20-30x performance gains in most areas on average. This gen is going to be very small leap all around Compared to usual. Due to dennard scaling nearing its physical limits, technology advances are slowing down. Its not a sudden stop, but a gradual slope. It will continue on this path until a new technology replaces silicon on insulator. We are constantly finding new avenues and technologies to scrape more power, but each new well we dip into is shallower than the last, and the greatest source of advancement, what moores law was based off of, and whats governed by dennard scaling, is slowing down. Moores law is no longer in effect... for soi technology. It had an impressive run, moore thought it would only last for 10 years. Its went for over 30 years. This is why sony and microsoft have extended their consoles longer than any generation in history.
It only takes some very basic computer engineering to understand whats going on. The gpu is extremely easy. Its absolutely massive, and on a process size less than half of xenos and rsx. With newer technology to boot.
The cpu is a little trickier to understand. Marcan doesnt know exactly how they compare clock to clock because hes never messed with xenon. I have.
Xenon is a heavily piped instruction architecture, with a very narrow execution core, and uses older static execution rather than having an execution window. This is because, back in that point of time, advancing by widening instruction cores was reaching a dead end.
So the execution core was narrowed dramatically, the processor was made in order, resulting in the need for devs to heavily optimize specifically for tge xenon to get the most out of the processors parallel executing abilities. This is very impiorant to remember, this entire generation is heavily HEAVILY optimized specifically for xenon. This is why ps3 multiplats have doo doo performance despire the cell being much more powerful.
These designs rely on heavy paralellization of code, so they have many simd nodes spreading the workload over many threads over many clock cycles, this means it is considerably slow ipc wise. However, sin e such heavily paralellization disperses the workload over many workers thrpugh a deep pipeline, it can be clocked much higher.
Wii u's expresso is a short Piped architecture, it is a MUCH wider execution core than xenon. It performs calculations with just one 'worker' in just one clock cycle. These are hard to clock high, but can outperform processors clocked much higher. This is why so much money was devoted to explaining the mhz myth, and when people ignored that, began 'comparative clock speeds' Where they would put on the box how high a competitors processor would need to be clocked to match performance.
So, explanations out of the way... heres the skinny.
Xbox 360 has 3 cores, with 2 threads a core. It gets 1 execution per thread. Thats 2 instructions per core x3 for 6 instructions a clock.
Broadway, not EVEN expresso but broadway, got six instructions a clock with just one core.
The problem was the huge disparity in clock speed AND the lack of multicore combined.
Broadway was an outdated ppc750cle when it realeased in 2006, in 2004 there were 750's that destroyed broadway, the 750gx and fx, which had over twice the transistors as broadway. None of these supported multicore or could be clocked as high as espresso.
If espresso is a gx or fx derivitive, which its physical footprint suggests (much too large to be a 750cxe at 32 mm square on a 45nm process) it would destroy broadway with just one core, at 749 MHz. But its 1.2 Ghz and tricore.
The problem is espresso and xenon are complete opposites. Also, there is no fp co processor, and simd wasnt focused on. So espresso actually has worse simd/fp performance, which are the building blocks of xenon optimization.
the answer to this is to use a different solution.
Since espresso is agressively out of order however, it can rearrange the code on its own, to get passable performance (worse than 360, better than ps3). Thats with code opimized for a processor with strengths that are wii u's weakness.
Wii u optimized games would be UNPORTABLE to 360.
so again with ipc... Xenon gets 6 executions per clock.
Espresso gets 6 instructions a core, with 3cores. Thats 18 executions a clock.
On top of that, xenon has to waste its resources on the games audio. Some games devote an ENTIRE CORE to audio. Thats 1/3rd the cpu.
Wii u has a seperate processor just for sound. No 360 ports use this.
360 cpu also has to handle system processes and the standby os.
Wii u has a multicore arm secure processor to assist with system and os tasks so cpu doesnt have to (this being utilized poorly may be the culprit for our os load times)
Wii u has 4 times the main ram (with 1Gb dedicated to games, a number likely to increase).
Wii u has a superior embedded ram, in capacity (massive increase) access speed and latency, with a smart memory heiarchy.
Edited by 3Dude, 08 January 2013 - 12:25 PM.
