Intel's Silverthorne (Ultra-Mobile Processor) Previewed

[MacRumors]

At this year's International Solid State Circuits Conference, Intel is giving additional details regarding its upcoming Silverthorne ultra-mobile processor (via News.com and AppleInsider).

According to the reports, Silverthorne will include dual in-order pipelines in order to keep power consumption at a minimal .5-2 Watts. Most modern chips use out of order pipelines for performance benefits, but at the cost of power. Nevertheless, AppleInsider says that the chip is expected to be as powerful as early Pentium M processors. Additionally, the processor will use the Core 2 Duo instruction set and will support hyperthreading.

Apple has been rumored to be adopting Silverthorne for their next generation iPhone. Silverthorne is expected to ship in the first half of 2008.

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[Eidorian]

Hyperthreading is back on ~Core 2! Why can't my other processors have it?

[calabi]

great news! 3g in the iphone now as well please!

[Muzzway]

I wonder what would be able to be accomplished with a more powerful iPhone.

[2A Batterie]

Originally Posted by Muzzway

I wonder what would be able to be accomplished with a more powerful iPhone.

For one, it would get me to whip out the Visa. Does anyone have an idea of when an updated iPhone will be released? Is this announcement an indicator?

[Eidorian]

Originally Posted by 2A Batterie

For one, it would get me to whip out the Visa. Does anyone have an idea of when an updated iPhone will be released? Is this announcement an indicator?

FCC documentation would be an indicator. I don't expect to see HD on the iPhone even with Silverthorne.

Does anyone else remember the hyperthreading rumors for Penryn? Anyone?

[lazyrighteye]

Originally Posted by Muzzway

I wonder what would be able to be accomplished with a more powerful iPhone.

Basically, a more robust experience/functionality.
Think more laptop less smart phone.

Why can't I shake this hunch that the iPhone is headed more towards a small, tablet-ish size/device than maintaining current 'smart phone' dimensions?

[happydude]

iphone 2 on it's way . . . sometime in June at WWDC?

now all it needs is 3G, ichat, GPS . . . watching the iphone evolve is like watching paint dry while on ecstasy - still is excruciatingly drawn out but so fun and exciting all at the same time!!!

[PlaceofDis]

thats pretty awesome. intel seem to enjoy working with apple and i wonder if apple put any ideas into their heads with this one.

[EagerDragon]

Originally Posted by PlaceofDis

thats pretty awesome. intel seem to enjoy working with apple and i wonder if apple put any ideas into their heads with this one.

Intel told us previously that Apple has been talking to them about how to look at Intel offerings differently. I think the Intel CEO said something similar to that.

When will this baby be available?

[sterlingindigo]

Originally Posted by lazyrighteye

Basically, a more robust experience/functionality.
Think more laptop less smart phone.

Why can't I shake this hunch that the iPhone is headed more towards a small, tablet-ish size/device than maintaining current 'smart phone' dimensions?

9" Macbook Air light

[numbsafari]

Originally Posted by lazyrighteye

Basically, a more robust experience/functionality.
Think more laptop less smart phone.

Frankly... I hope they don't go that route... I mean... I love my iPhone, but trying to do anything that involves writing even short messages is a real PITA.

I hope they continue to keep it smart and simple.

Why can't I shake this hunch that the iPhone is headed more towards a small, tablet-ish size/device than maintaining current 'smart phone' dimensions?

I hope they keep the iPhone where it's at... it's a good size for a phone. I don't want to hold a tablet PC up to my ear when making calls.

[MacFly123]

Originally Posted by lazyrighteye

Basically, a more robust experience/functionality.
Think more laptop less smart phone.

Why can't I shake this hunch that the iPhone is headed more towards a small, tablet-ish size/device than maintaining current 'smart phone' dimensions?

I can see them adding an additional product like that to serve more as the Next Gen Newton, but I don't think people want their phones any bigger. I would like them to make the iPhone thinner and smaller, as long as the screen stays the same size.

[Abstract]

Originally Posted by Muzzway

I wonder what would be able to be accomplished with a more powerful iPhone.

You can check your calendar.....but faster than ever. Phone calls will be faster. People will talk faster.

[BoyBach]

Originally Posted by Abstract

You can check your calendar.....but faster than ever. Phone calls will be faster. People will talk faster.

And all at the same time!

[sterlingindigo]

Originally Posted by Abstract

You can check your calendar.....but faster than ever. Phone calls will be faster. People will talk faster.

Fast talkers...that's right! I'm a low talker, would it help me? I mean, be louder?

[johnnyjibbs]

Originally Posted by Muzzway

I wonder what would be able to be accomplished with a more powerful iPhone.

More power for less energy is always better. Imagine smoother animations but with extra battery life.

Once the iPhone has 3G and bigger capacity, I'll be much more ready to get one.

[numbsafari]

Originally Posted by Muzzway

I wonder what would be able to be accomplished with a more powerful iPhone.

VoIP... on the hacked versions at least... and possibly real support for Flash...

[numbsafari]

Originally Posted by Muzzway

I wonder what would be able to be accomplished with a more powerful iPhone.

Oh yeah... and a real, multi-threaded Safari...

[twoodcc]

Originally Posted by Muzzway

I wonder what would be able to be accomplished with a more powerful iPhone.

im wondering that also. it seems the current iPhone is pretty powerful.

looking forward to it either way

[Jackal-Head]

Originally Posted by Eidorian

Hyperthreading is back on ~Core 2! Why can't my other processors have it?

How effective hyperthreading is depends on factors like the pipeline length and whether or not out-of-order execution is used. Intel designed the later Pentiums with one goal in mind: Higher clock speeds (at virtually any cost). The only way to achieve this was to use a very high pipeline length. The downside were more frequent and longer stalls than would occur on a processor with a shorter pipeline. Consequently, the utilization of the CPU's integer and floating-point units was sub-optimal. This means when Intel introduced hyper-threading to the Pentium 4, there was a need for a way to increase processor throughput by making more effective use of its integer and floating-point units.

AMD, on the other hand, wisely chose not to compete in this rat race. High clock speeds may be good for marketing to the technically unaware, but a better measure for a processor's speed is throughput: Clocks per second multiplied by the amount of work that, on average, can be completed per clock. Thus, in their Athlon series, AMD preferred to improve the CPU design to combine moderate clock speed increases with great increases on the work per clock side. This allowed AMD to use a shorter instruction pipeline, meaning less, and less severe stalls, and consequently better utilization of the processor's work units even when additional units were added. Also, the longer clock cycles allowed AMD processors to perform more complex calculations per clock. The net result was that Athlons would, in real life applications, often outperform Pentiums that operated at significantly higher clock speeds, attracting all sorts of tech savvy customers to AMD. It is obvious from the Athlon's short pipeline design that hyper-threading would have been much less effective on Athlons than on Pentiums, so it is unsurprising that AMD did not choose to introduce it on their CPUs.

Enter Paul Otellini whom I highly respect. He may not have been the one who started the "Core revolution", but he definitely supported it. But let me explain what I mean by this term. By 2005, it was becoming more and more obvious that Intel would have massive difficulties further increasing their processors' clock speeds. It was also obvious that even in the mid term, many of the problems were insurmountable. Plus, the power consumption of the Pentiums reached absurd levels even before Intel introduced the shame de la shame of the entire line - the Pentium 4 "Prescott". The NetBurst architecture had reached a dead end. Intel finally did the right thing and redesigned its processors to use shorter pipelines and perform more work per clock - just like AMD had done for years. Intel even did this at the expense of clock speed. In doing so, Intel managed to overcome the efficiency problem while at the same time improving processor throughput. At the same time, hyper-threading became largely obsolete - while allowing more than one thread to run simultaneously was still desirable, this would require increasing the number of work units as well rather than just allowing two threads to share the same set of work units like in hyper-threading. Thus, the Core Duo was born, and the rest is history.

In a sense, Intel finally realized it was on the wrong track and has now chosen to abandon NetBurst and out-AMD AMD instead. They had a lot of success doing this. This should also explain why now there are Intel CPUs with 4 cores but no hyper-threading.

But why would Intel then want to reintroduce HT in Silverthorne? Simple - while Silverthorne as a Core CPU could effectively saturate its work units by out-of-order execution alone, Intel chose to remove OOO execution in order to conserve power. But this means Silverthorne might suffer from the old work unit utilization problem, and hyper-threading becomes interesting again, at least for this particular processor line.

As an interesting foot-note to a long post, I want to add that hyper-threading can, in extreme cases, actually hurt processor throughput. This can happen when both threads taken together require more cache memory than is available (while there would be enough cache for just one thread). In this case, they will cannibalize on each other's cache, and the number of RAM accesses will skyrocket, causing frequent stalls and thus slowing down the processor's operation.

[Eidorian]

Originally Posted by Jackal-Head

How effective hyperthreading is depends on factors like the pipeline length and whether or not out-of-order execution is used. Intel designed the later Pentiums with one goal in mind: Higher clock speeds (at virtually any cost). The only way to achieve this was to use a very high pipeline length. The downside were more frequent and longer stalls than would occur on a processor with a shorter pipeline. Consequently, the utilization of the CPU's integer and floating-point units was sub-optimal. This means when Intel introduced hyper-threading to the Pentium 4, there was a need for a way to increase processor throughput by making more effective use of its integer and floating-point units....

...But why would Intel then want to reintroduce HT in Silverthorne? Simple - while Silverthorne as a Core CPU could effectively saturate its work units by out-of-order execution alone, Intel chose to remove OOO execution in order to conserve power. But this means Silverthorne might suffer from the old work unit utilization problem, and hyper-threading becomes interesting again, at least for this particular processor line.

As an interesting foot-note to a long post, I want to add that hyper-threading can, in extreme cases, actually hurt processor throughput. This can happen when both threads taken together require more cache memory than is available (while there would be enough cache for just one thread). In this case, they will cannibalize on each other's cache, and the number of RAM accesses will skyrocket, causing frequent stalls and thus slowing down the processor's operation.

I'm sorry for cutting your very informative post but I lived through it.

I'm sure other users would benefit from the history lesson. I'll just have to wait for Nehalem to see what Intel has in store for hyperthreading on x86 there.

[Amdahl]

Originally Posted by Eidorian

I'm sure other users would benefit from the history lesson. I'll just have to wait for Nehalem to see what Intel has in store for hyperthreading on x86 there.

My guess is nothing on the desktop. Hyperthreading & OOE should both be going away (as core counts rise). That's why it is curious that this chip only got rid of one, when they both use the same hardware on the chip.

[Eidorian]

Originally Posted by Amdahl

Hey gnasher & numbsafari! Better let Jackal-Head here know that he doesn't know what he's talking about!

Hmm.. very interesting. So there is some kind of relationship between OOE and Hyperthreading? Guess I'd better hit the Wikipedia so I can stop pissing on myself! From my skimming they both want to avoid letting stalls prevent the usage of execution resources.

In all seriousness, actually an excellent post. The decision to keep hyperthreading and drop OOE, must be based on some very app-specific factors, or the embedded space in particular, where hand optimization can be assumed.

I'm going to brush up on my OOOE and hyperthreading knowledge as well. From my skimming they both want to prevent stalls from slowing down the usage of execution components to complete a task.

Originally Posted by Amdahl

My guess is nothing on the desktop. Hyperthreading & OOE should both be going away (as core counts rise). That's why it is curious that this chip only got rid of one, when they both use the same hardware on the chip.

http://www.google.com/search?q=hyperthread%20nehalem

It should trickle down from the Xeons just like on Core 2 and Netburst.

[SthrnCmfrtr]

Originally Posted by Jackal-Head

....

Quite possibly the most informative and comprehensible post I've ever read on the Intel-AMD wars. Thank you.