Core Duo - Intel's Best CPU?

Bender writes "How good is Intel's Core Duo mobile processor? Good enough that Apple chose to put it in the iMac, and good enough that Intel chose to base its next generation microprocessor architecture on it. But is it already Intel's best CPU? The Tech Report has managed to snag a micro-ATX motherboard for this processor and compared the Core Duo directly to a range of mobile and desktop CPUs from AMD and Intel, including the Athlon 64 X2 and the Pentium Extreme Edition. The results are surprising. Not only is the Core Duo's performance per watt better than the rest, but they conclude that its 'outright performance is easily superior to Intel's supposed flagship desktop processor, the Pentium Extreme Edition 965.'"

Comments

Having used a Intel Dual Core for awhile ...

[Sonic McTails]

I have to say the Intel Dual Core Processor is quite impressive. It's fast enough to run just about anything I throw at it, and still keep chugging, but I believe that the article negects the fact that the dual core processor runs extremely hot vs other Intel processor. My old Sony VAIO never got as hot as my MacBook Pro does, and it is something that should be considered.

Re:Having used a Intel Dual Core for awhile ...

[phrasebook]

How important is heat, really?

Heat is a huge consideration to many people, often the deciding factor.

Assuming that the machine has been engineered sufficiently well to prevent the processor from melting down

It doesn't matter how well the machine is engineered. If you have hot componentry you'll have a hard time getting rid of the heat without making a lot of noise, especially under load.

But I never even considered not buying one because of the heat

What choice did you have? With laptops (especially Apple) you basically take what you can get. There's very little mention of heat or cooling considerations at all.

And no consideration at all to desktop buyers

I bought an Athlon X2 solely because it runs much cooler than the P4.

and in server rooms where it is a consideration... they'll have an A/C system anyway
The consideration is power consumption. More heat means more power draw means more expensive.

I doubt Intel is going to lose any customers because their chip gets too hot.

They lost me in the last round. Thankfully they're finally about to put the P4 to rest and we can get back to the good old P3. I mean, P-M. I mean, 'Core'. Whatever.

By the way, once you start caring about heat (and you will!) go here for starters: http://www.silentpcreview.com/

Re:Having used a Intel Dual Core for awhile ...

[NutscrapeSucks]

There's not a huge difference between Pentium-M and Core Duo due to the dieshrink.

Pentium-M 2.26GHz 90nm 27W
Core Duo 2.16GHz 65mn 31W

Of course, there's low-watt versions of all of these.

Re:Having used a Intel Dual Core for awhile ...

[Surt]

I have a dell inspiron 9300. They designed it so that the fans don't go up to high speed until it gets really hot (to keep the noise down I assume). Unfortunately, that means it reaches lap scalding temperatures before the fan comes on to cool it off. So although it is a 'laptop' it cannot actually be used on the lap for more than 15 minutes without injury. So heat does matter to some extent. My next laptop will not have this problem, because I won't buy one that does.

Re:Having used a Intel Dual Core for awhile ...

[Phroggy]

They have pathetic battery life after all the bragging Jobs did at last years WWDC.

The impression I got was that Jobs was trying really hard to avoid mentioning the battery life; the MacBook Pro was still in development and all they had were prototype models, so they actually didn't know what the battery life would be; they were guessing it should be "about the same" (as the PowerBook G4).

They are slow. My old G4 laptops kick the shit out it for media type tasks, about the same for single thread performance, and of course are slower for multi-threaded tasks.

Are you running all native applications? If not, it's not a fair comparison (and if you really need apps that aren't available natively yet, maybe you shouldn't have bought one yet). If you are running native apps, your experience seems to disagree with most reports I've heard.

It seems the speed most people are claiming for the MacBook Pros is due more to the faster video cards and the silky smooth desktop acceleration people weren't use to with their old G4 machines.

I'm really looking forward to this.

It is depressing to think that if Apple hadn't pissed off IBM that we could be running much faster/cooler dual core 970 PowerBooks right now.

If Apple hadn't pissed off IBM? When the G5 was released, Apple announced that they had 2GHz then, but would have 3GHz in one year. What was Apple supposed to do when that never happened? Just wait and hope that IBM figured out how to make something work?

Instead dual boot AMD Windows/Linux systems are looking like the only option for people who don't want to pay twice as much for x86 hardware.

Show me a laptop with comparable specs for half the price of a MacBook Pro. I think you're trolling.

Re:Having used a Intel Dual Core for awhile ...

[Midnight Thunder]

In a unit like the iMac, where there is plenty of air flow around the case heat is less of an issue, and you are not likely to spend your time with your hand on it. In a portable heat is a big issue, since the under side has zero air flow when on a desk, and on the upper side where heat is going to be noticed your hands are resting, for large amount of time.

Also, heat can actually reduce the life-span of components.

Re:Having used a Intel Dual Core for awhile ...

[darkwhite]

How important is heat, really?

Extremely important.

It's blindingly obvious why it is important in laptops - not only because of battery lifetime, but also because the cooling assembly size and weight depends on TDP, and of course for user comfort considerations. Intel started a mobile CPU revolution with the Pentium M, so it's a little disappointing to hear that its latest successor doesn't improve further.

It's just as blindingly obvious why heat is terribly important for servers, where rack heat and power density has long been the limiting factor to packing more servers into less space.

On desktops, to me personally, heat is a premier consideration when choosing any chip. I have no need for something twice as fast as my current CPU if it consumes twice the amount of power. I expect better.

Re:Having used a Intel Dual Core for awhile ...

[rekoil]

Let me interject here - I own a dual 1.8GHz G5 tower. Anyone who's looked inside one of these things has the same initial reaction - "god, those heatsinks are HUGE!". And while it's very quiet while idling, it does get noisy when it's under load. And you can feel the heat coming out the back if you put your hand back there. It's almost as bad as the dual Athlon XP system I used to have that would literally heat the room.

By contrast, I just got an IBM ThinkCentre desktop system at work, featuring a dual-core 2.8GHz Pentium D running Linux. The heatsink is a reasonable size, and the CPU fan is actually on the front of the tower chassis with a duct guiding the air over the CPU's heatsink. This thing is practically silent, and even when compiling a kernel with-j4 set you can't feel much hot air coming out the back.

The moral of the story is that IBM was waay behind Intel on the performance-per-watt game and had no signs of being able to catch up. People knew this well before the Intel switch was announced and so far there's no sign of Apple being proved wrong.

That said, anyone have any info on the heat dissipation on the dual-core G5s vs. the single core CPUs?

Re:Having used a Intel Dual Core for awhile ...

[Senjutsu]

Intel started a mobile CPU revolution with the Pentium M, so it's a little disappointing to hear that its latest successor doesn't improve further.

Wha?? Did you even glance at the article?

The Core Solo uses the same power as the Pentium-M to deliver more performance. The Core Duo uses slightly more power than the Pentium-M to deliver a lot more performance. Ergo, the performance per watt figures in both cases are better than the Pentium-M's.

In what sense, exactly, does the Core (Yonah) series not continue making improvements on its predecessors?

Depends

[2.7182]

I would argue that the 8080 was. If you normalize for date/speed that is...

Re:Depends

[Anonymous Coward]

I wrote micro interpreters at Infocom. My 1MHz Apple II 6502 interpreter was 80% fast as the 6MHz PC AT 80286 interpreter.

drewk

CoreDuo != Core Microarchitecture

[BobPaul]

It's not obvious from the article, but you can find it elsewhere on the internet (such as Intel's comment that the Core microarchitecture will provide 20% boost over CoreDuo). It is hinted at in the article with the following quote (emphasis mine).

If you've been hanging around here for a while, you may have heard us referring to Core Duo by its code name, Yonah, long before Intel decided to give it a somewhat confusing official name. ... In the case of the Core Duo, those CPU cores are massaged and tweaked versions of the Pentium M processor, familiar as part of Intel's Centrino mobile platform.

The new core microarchitecture, if you read the Ars Technica article in the previousl /. posting linked, was designed from the ground up and is similar to PentiumM in many respects, but is much more different than the CoreSolo and CoreDuo are.

Re:CoreDuo != Core Microarchitecture

[MrFlibbs]

The new Merom-based products (Conroe is the desktop version) were *NOT* designed from the ground up. The Ars Technica article repeated some Intel marketspeak that overstates the case. Merom is a major revision of Yonah, but is derived from the same code base. In fact, it is still technically a derivative of the P6 family that began with the Pentium Pro 10 years ago.

This is more than just a matter of semantics. The major micro-architectural features that defined the P6 are still present in Merom. The P4 architecture (may it rest in peace) was a brand new architecture -- Merom is not.

Re:CoreDuo != Core Microarchitecture

[uarch]

Yeah, they use both HDL coding and EDA (cad-like) tools to design most microprocessors. The designs are too massive to design them by placing each wire manually - they haven't done that for _several_ generations (1980s? - not sure really)

That's not to say there isn't a small army of design engineers at Intel and AMD who work with nothing but schematics - there are. Its just that most of the logic design work is done on the HDL coding level (with either VHDL, IHDL, Verilog, or some other tool). You only start dealing with schematics at a much later stage of development. Until then your designs are constantly changing and its infinitely easy/faster to change a few lines of HDL code than to re-write hundreds/thousands of wires and transistors.

I've worked at both Intel and AMD in the past and in both cases you could take the entire codebase for a processor (HDL, microcode, ROM, etc), compile it with the right HDL compiler and run the entire thing with small test programs as a simulator. Thats how much of the validation/verification work is done before they make the masks.

As for using the old code bases... That's done a lot. There's just too much complexity and too little time for them to re-write every processor from scratch. You also have countless hours invested in making sure previous designs work. If you're only doing small changes it would be hard to justfy building something from scratch since you'll have to do all of that validation work again.

Hotter the Better

[dueyfinster]

You're forgetting all those students with Laptops, one I know said his laptop was so hot, he'd leave it on his bed before going to sleep, as the accommodation had substandard heating (the norm for all student places, no?)

Even more reviews

[adam1101]

More reviews here and here.

Common Knowledge

[John Jamieson]

I thought this was commonly known or assumed. Is this news to many people?

I thought that the only reason the P4 had not been totally abandoned already was that it takes time to switch directions in such a massive company. (and with so many partners that design around your product)

If those figures...

[c0l0]

...actually show ANYTHING really well, then it's the absolute neglibility of recent synthetic benchmarks. Looking at the numbers SiSoft Sandra spills out, the clocked-to-the-brim Netburst-cores should take the performance-crown with ease in FPU and ALU-applications alike. In reality though, said CPUs hardly matter at all when it's about uncompromising peak-performance. I fail to understand why benchmark-suites this far away from reality still matter in reviews like this.
Sad, in an awkward way.

What?

[plantman-the-womb-st]

Core Duo is a 32bit processor.
Athlon 64 X2 is a 64bit processor.

I care not how much power it uses or how well it runs Word or whatever else they are doing to test these things.

The Core Duo cannot do the same things the Athlon 64 X2 can. Largely because (gasp) it cannot run 64bit code.

What the hell is the point of this comparison?

Re:What?

[DrDitto]

The reason for going to 64-bits is to increase the amount of physical address space, not for speed. The majority of applications, especially integer, do not benefit from bigger registers and wider ALUs.

Re:What?

[Jeff DeMaagd]

Actually, x86-64 does have some speed benefits over standard ia32 for smaller programs and data sets in that it doubles the number of exposed registers. Most other archs were not register starved on the 32 bit version, so going 64 bit generally slowed the system down a bit because the pointer size doubled, taking more memory bandwidth to store pointers.

Re:What?

[Phroggy]

The Core Duo cannot do the same things the Athlon 64 X2 can. Largely because (gasp) it cannot run 64bit code.

What the hell is the point of this comparison?

You're correct, of course. However, many of us don't need to run 64-bit code. You can completely ignore this, because any 32-bit CPU doesn't fit your needs, but please try to understand that other people need different things.

Re:What?

[Anonymous Coward]

The Core Duo cannot do the same things the Athlon 64 X2 can. Largely because (gasp) it cannot run 64bit code.

I drive an 18 wheeler, and I can't imagine why anyone would want a passenger car. You can't haul near the same amount of goods!

Re:What?

[darkmeridian]

Hate to say this, but there are not that many uses for 64 bit processors yet. Manufacturers do not provide 64-bit drivers for their products. The drivers that exist are buggy. To the average Joe, 64-bit is useless. He doesn't need the extra horsepower for his Internet browser or word processor. Well, unless Vista comes out.

Re:What?

[Mark Gillespie]

Who wants a EMT64/AMD64 in a mobile processor? it serves no purpose. I think the AMD fanboys are realising that the sleeping giant is waking up...

Re:What?

[NutscrapeSucks]

The "more registers" with x86-64 has been massively overhyped. There's very little real world benefit.

For example: AMD's claims about UT2004 being 20% faster in 64-bit mode turned out to be bogus (more like 2%).

Re:What?

[AcidPenguin9873]

x86 processors since the Pentium and the Am586 have more registers than they expose, and when you perform a context switch, they can swap in the other registers, meaning they can cut the time of a context switch down a great deal.

Register renaming has nothing to do with context switches. The "invisible" registers are used to remove false dependencies in the instruction stream to increase Instruction-Level Parallelsim (ILP) within a single thread. In fact, on a context switch, the architectural state exactly matches the physical state (no "invisible" registers are in use), and so the processor doesn't have to save any extra registers other than the architecturally-visible ones. The details (skip if you're not interested):

loop:
movl %ecx, (%ebx)
# Do something complicated with ECX
addl $4, %ebx
cmpl $64, %ebx
jl loop

In the above assembly, the instructions are dependent upon one another: you can't execute the incl until after the movl because the incl overwrites EBX. You can't start executing the next iteration of the loop until the current iteration is finished, because the movl at the top of the loop overwrites ECX. These restrictions only arise because you are reusing the registers EBX and ECX. If you could somehow use different "copies" of these registers, you could execute multiple iterations of the loop in parallel, and execute instructions inside the loop out of order.

Inside the processor, the instruction stream may be seen like this:

%r0 <- (%r1)
# Do something complicated with r0
%r2 <- %r1 + 4
cmpl $100, %r2
jl loop

%r3 <- (%r2)
# Do something complicated with r3
%r4 <- %r2 + 4
cmpl $100, %r4
jl loop

...

The processor has removed all false dependencies by using its internal, non-visible registers to remap different loop's "instances" of EBX and ECX to different physical registers. This enable out-of-order execution: since the next "copy" of EBX has been renamed to be a different physical register (r2) than the original value of EBX (r1), the processor can execute the addl instruction LONG before it executes the "Do something complicated" portion of the loop.

This then allows the processor to execute multiple iterations of the loop in parallel (with branch speculation and recovery) by performing the addl instruction very soon after the loop begins, which will allow further iterations of the loop to run by calculating the "next" value of EBX. The processor has effectively performed loop unrolling in hardware.

Benchmarks

[SilentChris]

I already posted some benchmarks of a Core Duo Mac Mini running Windows (http://slashdot.org/comments.pl?sid=182379&cid=15 077120) and to be honest I was fairly impressed. The gaming benchmark was obviously miserable, the "general purpose" benchmark (zipping files, encoding audio/video, etcdid very well. The Apple zealots may say "it's because it's a Mac", but really the hardware is almost identical to your average Intel laptop. The only major difference is the Core Duo, which not many laptops have (although that's increasing all the time), and that's what I'm putting my money on. Can't wait to see a benchmark with this thing in a gaming rig.

No way!

[thetaco82]

So, Intel's new 65nm process is better than their older processes? Weird...

Take note! Many of these features inside AMD too.

[Inoshiro]

"But Yonah also supports the group of 13 new instructions known as SSE3, handles some SSE2 instructing like Shuffle and Unpack up to 30% faster, and is capable of using its instruction-grouping abilities (known as micro-ops fusion) on some SSE instructions, improving overall throughput."

SSE3 has some very nice hardware thread synchronization instructions. These are important (and AMD has them now). As for the instruction grouping, that sounds rather suspiciously like the double dispatch operations that were added to Opteron:
"Appendix C of Opteron's Optimization Guide specifies to which class each and every instruction belongs. Most 128 bit SSE and SSE2 instructions are implemented as double dispatch instructions. Only those that can not be split into two independent 64 bit operations are handled as Vector Path (Micro Code) instructions. Those SSE2 instructions that operate on only one half of a 128 bit register are implemented as a single (Direct Path) instruction."

Assuming AMD can tune Turion64s to be more power friendly, they'll be able to best Intel's fancy new Core Duo. If they can't, then Intel may be the best game in town for the first time in a decade (assuming they price competitively).

Maybe per watt performance is the best but...

[danpsmith]

Looks like AMD still has them beat. From my take on this, on pure performance, the 3800+ X2 is going toe-to-toe and the 4800+ X2 is beating it every single time. So again, not that impressive. Now the per watt performance is important in some applications, so I can see why it would be a better, say, mobile platform than the AMD chips. But let's not pretend that Intel is winning the benchmarks with this quite yet.

Re:Maybe per watt performance is the best but...

[Sebastopol]

But let's not pretend that Intel is winning the benchmarks with this quite yet.

'Yet' is now.

Merom/Conroe defeats AMD-AM2 hands down, and AMD has nothin' on the roadmap for the next two years, because AM2 slipped a full 12 months.

Go surf around Anandtech.com

AMD is in deep doo doo.

Re:Maybe per watt performance is the best but...

[Senjutsu]

So what would you do if you wanted a dual core 64 bit laptop?

Realize that there isn't a laptop on the planet that can make use of a 64 bit address space, and come to my senses?

The 8080? No way! The Intel 4004 was smokin' hot!

[dpbsmith]

At the time it was introduced, there was no other microprocessor that came close to matching it.

It was indisputably not only the best microprocessor Intel had produced to date, but the best microprocessor on the market.

Simply no contest. No argument. It superlative in every way, the fastest, the cheapest, the lowest in power consumption, the most advanced in architecture, the widest path. It was king of the hill, the top of the tree, the Cadillac of microprocessors, the ne plus ultra, it bestrode the world of microprocessors like a colossus.

The world will never again see the day when one manufacturer so dominated the microprocessor market that a single product had a 100.0% market share.

Re:Load of Crap

[NCG_Mike]

Our QA department is testing my universal application right now (AppKit based). They've recorded a 20 to 30 percent increase in performance of a 1GB MacBook Pro over a 3GB 2Ghz Dual G5 doing a particular operation (mostly mathematics based done in cross-platform C++). It's single threaded, I might add, since OpenMP isn't here yet. The *ONLY* difference in the XCode settings between the two architectures that I made was to enable SSE3 for the Intel build. I can't believe that it's that alone, of course, and suspect it's just better code gen for the Intel architecture coming out of GCC.

Mhz War AMD vs Intel

[vchoy]

From the article: ...The T2600 can't quite take the overall performance crown from the likes of the Athlon 64 FX-60 or the X2 4800+, but jeez, it's startlingly close....

Given the T2600 runs at 2.16ghz

Compare this to

AMD 4800+ 2.4ghz

it really does seem the 'Mhz = performance' is well and truely over...and for the first time Intel seems to be saying to AMD "We too can play your Mhz mean 'nuffin game'"

Again...the test results maybe affected by the chipsets used for the different processor architectures, which in turn affected the the types of memory used (DDR2/DDR) etc etc...

Practical experiance

[weiserfireman]

Just this week, I received a brand new HP nx9420 laptop with a 1.83Ghz Duo processor. I use this laptop for 3D Solid CAD/CAM applications. For my application, it is definately faster. The CAM rendering is faster, the part rotation is smoother. Overall very efficient. I have done some stress testing by doing some long database queries at the same time I am rendering a part. My old computers would have joked. There is a noticable hit on rendering performance, but it is still able to complete both tasks in a reasonable manner. We have the same CAD/CAM software on a 1.6Ghz PentiumM Laptop and two 2.8GHz Pentium-4 desktop machines. All the machines have 1024MB of RAM, and the two Desktops have 256MB video cards. I have not noticed that heat issues that other folks have mentioned, but I don't hold it in my lap either. So far I am very impressed.

Re:The real test will be time...

[Anonymous Coward]

The parent is the worst comment I have ever seen. Maybe my morning coffee hasn't kicked in yet.

"It might perform well now, but how long will it last under a load? Will something happen over time that they do not forsee?"

Of AMD Competition? Of continuous 100% CPU utilization? Of OEM bumblings putting on an improperly rated Heatsink fan? If there is any faith in Moore's law, then we will all come to the simple conclusion that this chip is not going to be the best forever. However, is it the best right now? Yes.

Performance per watt, per cycle, overall execution speed have proven this chip is the best x86-derieved architectures. This is a great accomplishment for Intel who's been on the ropes for quite some time.

Now, to say, "Well, they may randomly explode because Intel pushed the envelope too far, I'm going to sit on my hands for another 6 months and wait out the war," is just caution to a fault. Yes, things will happen that people don't forsee. Will it explode? Will it have catastrophic microcode failures which cause hardware damage? Maybe. But then again, you'd just be sitting on your hands waiting for the off chance that you are right.

p.s.
Long time reader, first time poster. Congratulations your post dragged me kicking and screaming into /.

Re:Load of Crap

[nsayer]

It is not faster than the G5 period!

It sure the hell is. I have a 2.0x2 G5 desktop machine and one of the new 1.66 GHz Core Duo Mac Minis. Running Handbrake, the mini is easily twice as fast.

Battery life in the MacBooks?

[delire]

Not only is the Core Duo's performance per watt better than the rest [...]

Why then is the battery life in the MacBooks so miserly?

What is AMD going to do?

[mcbridematt]

I think its extreme pricewhore time for AMD, apart from a new Socket with DDR2 - which solves a problem which has never really existed at AMD* (I still enjoy my Opterons NUMA as much as the next person though :) ), although DDR2 still brings some benefits none the less.

* Apart from the Athlon MP, whose usefullness apart from a low low cost SMP server platform disappeared when stuff started to demand more bandwidth. A Uniprocessor Duron on an nForce2 owns it on anything where AGP and memory bandwidth comes into play!

Re:The 8080? No way! The Intel 4004 was smokin' ho

[Anonymous Coward]

Son, I say, son, that's a joke, son, when it was the first microprocessor on the market, with no competitors. By definition, it would be the fastest, cheapest, coolest, et cetera, as there is nothing else for means of comparison.

Goddamn, are all the UIDs over 500000 stupid 13-year-old kids who don't understand English?

Re:Load of Crap

[wvitXpert]

I wish there was a mod option for 'Blatantly Incorrect'.

Keep in mind that

[sgent]

Intel's lead is mostly a manufactoring one -- 65nm process. AMD still uses 90nm. Not to discount Intel's advantage, but AMD doesn't need a new core design to continue their dominance -- merely a new manufactoring facility (which is hard, but not as hard as the design).

Re:Keep in mind that

[Asic Eng]

Are you sure about that? I would think it's just the opposite. This article gives the costs of the AMD 65nm facility in Dresden as $2.4 billion over 4 years. I'd be surprised if the digital design expenditure would look significant in comparison. That said, it looks like the fab should come online this year, so Intel won't have that advantage for long. If they were just starting to develop a 65nm facility now, I'd be very worried for them, though.

Re:Keep in mind that

[ciroknight]

The problem is, Intel is way ahead on their 45nm manufacturing process, which could virtually negate AMD's 65nm step. (Intel says they're going to be ready in 2007, which is when everyone expects the new AMD 65nm fab to come online).

If Intel could get to 45nm before AMD even gets to 65nm, you could kiss any performance gain that 65nm would lend AMD totally goodbye. (There's no telling how likely it is that this could happen, but seeing as both Intel and AMD are putting a great deal of their resources into it, it's anyones guess).

Heat is a problem

[nephridium]

Even if the notebook was engineered well enough (additional cost) to dissipate the heat fast enough from the CPU there are still several downsides having a hot notebook. You have to consider that the more heat the CPU produces the more will spread through conduction all over the notebook, no matter how well it's engineered. This will cause

• the overall life expectancy of electrical components to degrade (HDDs, RAM come to mind, and basically anything that uses caps)
• the LiIon batteries to die earlier (it's annoying to see the capacity dropping within months of use replacing them is still quite expensive)
• your lap to fry unless you use an insulator such as a telephone book or you restrict yourself to the tabletop

But if the CPU architecture really is that good, it should be easy to make a cool low voltage version that still has enough power to.. say... run Windows Vista (scnr ;)

As a slashdotter this probably doesn't concern you

[nikanj]

But laptop heat is a major threat to male fertility. See this article for more details.

Hard-Core

[leabre]

I'm waiting for the Intel Hard-Core Extreme Edition: Keep your servers up and running all night, watch them scream.

Uhmmm... count me in.

Thanks,
Leabre