By using this site, you agree to our Privacy Policy and our Terms of Use. Close
snowdog on 23 September 2013
Edit Thread
forethought14 said:
fatslob-:O said:

@Bold here's where your wrong, Jaguar features wider SIMD units as evidenced by its AVX extension while also having wayyy more than 2cores.

Can I like also get some source on how those cores are based off of a G5 please ?

Developers probably have strip some workloads for the wii u processor to get it running. How do you think developers got games running on older consoles ?  BTW the CPU isn't all important for purposes of of rendering today. 

can you like show some evidence as to the figures for JAGUAR AND NOT BOBCAT are close to the espresso.

BTW those were comparisons Whether you like it or not I can still accept the fact that it has a weak cpu plus I'm seriously worred about the WII U in the future unless ofcourse nintendo drops support easily.

Jaguar is a 4-core CPU, with 2MB of cache and performance enhancements with new instructions added from Bobcat, that's it. Obviously a Jaguar CPU alone would best a Bobcat CPU since there are more cores, and they have 15% higher IPC, 128-bit SIMD instead of 64-bit, and new instruction sets, but this is NOT going to do much to increase overall performance per-core the way you think. You will not see anything near double the performance out of this because it's only the SIMD width that increased by 2. Real world performance (factoring everything in), will be a bit over 50% more powerful than Bobcat. Again, I'm talking about "per core". 

And an 8-core Jaguar goes at 102.4GFLOPS. 2 cores are reserved for the OS in PS4/X1. 8 FLOPS per cycle, per core. 8 x 1.6ghz = 12.8 GFLOPS per core. 6 usable cores = 76.8 GFLOPS for PS4 CPU, 84 GFLOPS for the X1 CPU (8 x 1.75ghz x 6)

Xenon is based on PPE, which is a PowerPC970, which is a G5. The PPE in Cell is a PowerPC970, which is a G5. G5s were designed to have high clocks, not so high IPC, improved SIMD performances, but they are in-order processors. Here's a link with a good explanation for both:

http://lowendmac.com/ed/bashur/12db/g5-gaming.html

No I can't, because no one has tested Jaguar yet. But if we look at this:

http://semiaccurate.com/assets/uploads/2012/08/slide-1-728.jpg

We can take into account the enhancements from Bobcat, and easily make the calculations from the test blu made in NeoGaf. Those numbers I gave you for Jaguar aren't going to change much (they are probably higher, but likely only about 15-20sh % higher due to the 128-bit SIMD, newer instructions and increased cache). You can also add a bit to the numbers on Espresso as well, considering how there is more cache in it compared to Broadway and it's lower-latency cache eDRAM (I based the Espresso numbers on a 256KB Broadway. Remember that 2 Espresso cores have 512KB of cache, and one has 2MB of cache (as much cache as one Jaguar CPU), that will also add a bit to performance, probably around 5%+/-). But still, the fact that it's that close to Jaguar core-for-core says a lot about how efficient Espresso is. Of course, the advantage the PS4/X1 CPUs will have over Espresso is obviously core count, newer instructions and a 128-bit floating point unit, but core-for-core, it's not goint to blow Espresso away. 

But anyway, this isn't a thread to discuss the CPUs in PS4/X1, this is about Wii U, so I'm gonna stop here. 



Great post, but thought I'd add two important things. Firstly that Expresso has a ridiculously short pipeline (4 stages!) and Jaguar has a 17 stages, so over 4 times more stages to do before a process is completed and secondly that Expresso also has access to 32MB of eDRAM in addition to the 3MB of CPU cache.

The second point above is HUGE.