Discussion: SoC vs CPU

[anbello262]

Hello everyone,
I have a somewhat difficult question today. I know there are not many points in common as each piece of hardware has their own distinctive market and firmware/software support is completely different, but:
I'm curious about the real capabilities of modern SoCs, like the newest Snapdragon, or Apple's A7. I've seen lots of reviews about those and I have investigated a lot about what they can do compared to each other, but I would like to have a real reference by comparing a SoC with a destop CPU.
For example, lets take Samsung's Exynos 5 octa, or Snapdragon 800. Would it be comparable to an entry level desktop processor?
Is its processing power similar to that of a low level desktop one (Intel atom for example), or is it as high as a mid range CPU?
Or maybe a SoC is not een comparable to a lowest level cpu? Maybe similar to an older cpu?

So, if I were to compare highest end SoCs with desktop CPUs, where should I put the SoCs?

 

[FromTheDepths]

Well, an A7 gets about a 2500 on Geekbench, where an Athlon II will run anywhere from 5 to 10k.
In other words, SoCs still pale in comparison to even the cheapest of desktop CPU's.

 

[jaguarskx]

SoC simply means System on Chip which is the integration of many functions that used to be performed by many other chips in to a single chip. Qualcomm is the current leader in SoC integration. Having said that desktop CPU has been following this route as well over the years like the inclusion of the memory controller and GPU core into the CPU itself. The latest integration is the voltage regulator module which was formerly on the motherboard into the Haswell CPU architecture.

I suppose your real question is how does ARM processors stack up to x86/x64 CPUs found in desktops. From a pure processing power point of view, there is simply no contest between something like the FX-8350 / i5-4670k and a quad core Snapdragon ARM CPU. Additionally, ARM CPUs cannot process complex instructions that a x84/x64 CPU can which partly explains why ARM processors do not need to have anywhere near the same number transistors found in a desktop PC. They are simply meant for a different type of processing.

ARM processors would be more equal to AMD's Temash/Kabini APU which is based on the Jaguar core. I don't recall which on (Temash or Kabini) is supposed to be used in tablets to compete with ARM process, so from here I will just use Kabini. Intel's competitor to the ARM processors is the Bay Trail generation Atom CPU. Both Kabini and Bay Trail are still x84/x64 so they run can run full Windows which means they are still pretty complex CPUs.

Unfortunately, for AMD there has not been any tablet wins for Kabini even though it was released back in May 2013. However, the release of Intel's Bay Trail Atom CPU opened up with the release of 8" Windows 8.1 tablets by Dell (Venue 8 Pro), Lenovo (Miix 8) and Toshiba (Encore). One of the main issues with complex CPUs is that because they have more transistors, they also tend to draw more power. One way to lower power consumption is by lowering the performance. Another way is to shrink the size of the transistors. And a 3rd way is to improve the CPU architecture itself so that it can process more instructions than previous generations.

AMD did not have any tablet design wins because in order to keep power consumption down, they had to lower performance. No one was impressed by Kabini's performance given the low voltage. Yes, perhaps on paper it may have seen that the performance might be competitive, but just because something might look competitive on paper that doesn't necessarily mean it will be and there was no reason for any tablet OEM to choose AMD's Kabini APU. Actual benchmarks and user reviews of netbooks with the Temash / Kabini APU has been at best lackluster. It seems AMD sacrificed too much performance for low power consumption.

On the other hand Intel's Bay Trail seems to have taken the tablet market by storm with the current 3 Win 8.1 tablets. Acer and Asus are releasing their Win 8.1 tablets next year. Some articles have even said that Bay Trail is Microsoft's savior for the Win 8 operating system. Just based on raw CPU processing power Bay Trail is still more powerful than ARM processor just based on the fact that Windows OSes have complex instructions that an ARM processor simply cannot deal with. Bay Trail more or less has about 2x more performance than their previous generation Atom CPU which I think was called Clover Trail.

What would be interesting are Android tablets running on tablets with Bay Trail Atom CPUs. They are expected to be released in 2014 after Intel has perfected their translation layer software which allows Android OS to run on Bay Trail. The more efficient the translation layer, the less performance loss there will when it translates instructions issued by Android OS to instructions that the CPU can process. This is not an Android emulator for Windows that allows you to run Android within Windows. This will be a "pure" Android OS tablet using a Bay Trail CPU. It would be nice though if you dual boot Windows and Android on a Bay Trail tablet. There are already people working on Linux for Windows tablets.

 

[anbello262]

Thanks for the reply, It was really complete and explained a lot. And yes, I meant ARM processors, thanks for the correction.
By merging both of your replies together (the first one was a lot more aimed at my question, and the second one explained a lot).
And of course I didn't mean to compare a high end CPU like 467 ARM0k with ARM based processors, I was aiming at something more modest, like what FromTheDepths proposed.

I was wondering all of this because I saw Dead Trigger, which has good graphics, being played on an iPad very fluently (yes, I know it has a lot more to do with the graphics processing part), and it made me really curious as to what would it take for a desktop PC to be able to play a game with similar complexity.
I know that Android games are mainly optimized for ARM based architecture, so a direct comparison can't be made, but still I waned to know more.

What I wanted the most was to have a [k]real[/k] reference point when speaking about ARM processors,and that reference point would be Desktop CPUs.