8 replies to this topic

[Matt]

Intel shows 45-nm processor

Mark LaPedus
(01/16/2007 6:07 PM EST)
URL: http://www.eetimes.c...cleID=196901271

SAN JOSE, Calif. — Intel Corp. on Tuesday (Jan. 16) said that it has completed the development of its next-generation, 45-nm process technology.

Intel also said that it has produced samples of Penryn, the company's first 45-nm microprocessor. In a system, the chip booted up various operating systems — such as Windows Vista, Mac OS X, Windows XP and Linux — using first silicon, according to Intel, which disclosed the milestone in its earnings release issued Tuesday.

The 45-nm process is scheduled for production in the second half of 2007 and will ramp to three 300-mm factories in 2008. ''These are good indicators of how healthy our 45-nm manufacturing and future product designs are looking so far,'' according to an Intel spokeswoman.

Seeking to get a jump on its rivals, Intel last year disclosed the initial details of its 45-nm process and claimed that it has produced the world's first chips based on the technology.

The 45-nm process will be used to make Penryn and other products, which are based on the company's next-generation Core architecture.

''Since late June, we have introduced almost 30 server, desktop and laptop processors based on the Core Microarchitecture, with the majority coming earlier to market than we first forecasted to our customers,'' the spokeswoman said. ''Nine of those are quad-core server and desktop processors for in just over two months since our first launch.''

Playing catch-up with Intel, rival Advanced Micro Devices Inc. has tipped the first technical details of its 45-nm process technology.

[doug123]

Whoa, 45 nm! I remember when Intel released the Prescott 90nm CPU and ditched the 130nm Northwood -- Prescott required more power than Northwood and also a MUCH longer pipeline (31 stages instead of 20!) and longer latencies...what a waste.

http://www.anandtech...doc.html?i=1956

The Pentium 4 has come a long way since its introduction in the Fall of 2000. It went from being a laughable performer, to a CPU embraced by the community. Today Intel is extending the Pentium 4 family with the third major revision of the chip – codenamed Prescott.

Back when Prescott was nothing more than a curious block on Intel’s roadmap, we assumed that history would repeat itself: Intel would move to a smaller, 90nm process, double the cache and increase clock speeds. Intel has always historically behaved this way, they did so with the Pentium III and its iterations, and they did so with the first revisions of the Pentium 4. What we got with Prescott was much more than we bargained for.

Intel did move to a 90nm process, but at the same time didn’t produce a vastly cooler chip. Intel did double the cache, but also increased access latencies – a side effect we did not have with Northwood. Intel also moved to Prescott in order to increase clock speeds, however none of those speeds are available at launch (we’re still no faster than Northwood at 3.2GHz) and Intel did so at the expense of lengthening the pipeline; the Prescott’s basic Integer pipeline is now 31 stages long, up from the already lengthy 20 stages of Northwood. With Prescott, many more changes were made under the hood, including new instructions, some technology borrowed from the Pentium M and a number of algorithmic changes that affect how the CPU works internally.

If you thought that Prescott was just going to be smaller, faster, better – well, you were wrong. But at the same time, if you view it as longer, slower, worse – you’re not exactly on target either. Intel has deposited a nice mixed bag of technology on our doorsteps today, and it’s going to take a lot to figure out which side is up.

Let’s get to it.
...

31 Stages: What's this, Baskin Robbins?

Flip back a couple of years and remember the introduction of the Pentium 4 at 1.4 and 1.5GHz. Intel went from a 10-stage pipeline of the Pentium III to a 20-stage pipeline, an increase of 100%. Initially the Pentium 4 at 1.5GHz had a hard time even outperforming the Pentium III at 1GHz, and in some cases was significantly slower.

Fast forward to today and you wouldn't think twice about picking a Pentium 4 2.4C over a Pentium III 1GHz, but back then the decision was not so clear. Does this sound a lot like our CPU design example from before?

The 0.13-micron Northwood Pentium 4 core looked to have a frequency ceiling of around 3.6 - 3.8GHz without going beyond comfortable yield levels. A 90nm shrink, which is what we thought Prescott was originally going to be, would reduce power consumption and allow for even higher clock speeds - but apparently not high enough for Intel's desires.

Intel took the task of a 90nm shrink and complicated it tremendously by performing significant microarchitectural changes to Prescott - extending the basic integer pipeline to 31 stages. The full pipeline (for an integer instruction, fp instructions go through even more stages) will be even longer than 31 stages as that number does not include all of the initial decoding stages of the pipeline. Intel informed us that we should not assume that the initial decoding stages of Prescott (before the first of 31 stages) are identical to Northwood, the changes to the pipeline have been extensive.

The purpose of significantly lengthening the pipeline: to increase clock speed. A year ago at IDF Intel announced that Prescott would be scalable to the 4 - 5GHz range; apparently this massive lengthening of the pipeline was necessary to meet those targets.

Lengthening the pipeline does bring about significant challenges for Intel, because if all they did was lengthen the pipeline then Prescott would be significantly slower than Northwood on a clock for clock basis. Remember that it wasn't until Intel ramped the clock speed of the Pentium 4 up beyond 2.4GHz that it was finally a viable competitor to the shorter pipelined Athlon XP. This time around, Intel doesn't have the luxury of introducing a CPU that is outperformed by its predecessor - the Pentium 4 name would be tarnished once more if a 3.4GHz Prescott couldn't even outperform a 2.4GHz Northwood.

The next several pages will go through some of the architectural enhancements that Intel had to make in order to bring Prescott's performance up to par with Northwood at its introductory clock speed of 3.2GHz. Without these enhancements that we're about to talk about, Prescott would have spelled the end of the Pentium 4 for good.

One quick note about Intel's decision to extend the Pentium 4 pipeline - it isn't an easy thing to do. We're not saying it's the best decision, but obviously Intel's engineers felt so. Unlike GPUs that are generally designed using Hardware Description Languages (HDLs) using pre-designed logic gates and cells, CPUs like the Pentium 4 and Athlon 64 are largely designed by hand. This sort of hand-tuned design is why a Pentium 4, with far fewer pipeline stages, can run at multiple-GHz while a Radeon 9800 Pro is limited to a few hundred-MHz. It would be impossible to put the amount of design effort making a CPU takes into a GPU and still meet 6 month cycles.

What is the point of all of this? Despite the conspiracy theorist view on the topic, a 31-stage Prescott pipeline was a calculated move by Intel and not a last-minute resort. Whatever their underlying motives for the move, Prescott's design would have had to have been decided on at least 1 - 2 years ago in order to launch today (realistically around 3 years if you're talking about not rushing the design/testing/manufacturing process). The idea of "adding a few more stages" to the Pentium 4 pipeline at the last minute is not possible, simply because it isn't the number of stages that will allow you to reach a higher clock speed - but the fine hand tuning that must go into making sure that your slowest stage is as fast as possible. It's a long and drawn out process and both AMD and Intel are quite good at it, but it still takes a significant amount of time. Designing a CPU is much, much different than designing a GPU. This isn't to say that Intel made the right decision back then, it's just to say that Prescott wasn't a panicked move - it was a calculated one.

We'll let the benchmarks and future scalability decide whether it was a good move, but for now let's look at the mammoth task Intel brought upon themselves: making an already long pipeline even longer, and keeping it full.

...

An effortless overclock gave us 3.72GHz; we could POST at 4GHz but we didn’t want to showcase what was ultimately possible with Prescott, rather what was easily attainable without increasing voltages.

Intel could have launched Prescott at higher clock speeds than they did, however it seems that their desire to produce as many mainstream Prescotts as possible (2.80E in particular) won out in this case.

Update: Intel has released the official thermal data on Prescott:
Thermal Design Power 
Northwood (2.8 - 3.4GHz) 69 - 89W 
Prescott (2.8 - 3.4GHz)  89 - 103W 

As we mentioned before, if you thought Prescott was going to be cooler running you'd be wrong. Prescott is one hot running CPU, now keep in mind that these aren't actual production thermals rather Intel's guidelines to manufacturers as to what thermals they should design cooling for. Needless to say, Prescott at 2.8GHz will be about as hot as a 3.4GHz Northwood. When Intel ramps up beyond 3.6GHz we'll definitely see some larger heatsinks being used on Pentium 4 platforms; some of the preliminary cooling setups we've seen for Tejas were insane.

Now that AMD and Intel have both gone dual core, I hope Intel can learn to keep their temps under control. I don't like my electricity bill to make me go broke.

Edited by nootropikamil, 19 January 2007 - 12:17 AM.

[chubtoad]

How much is it going to cost?

[Ghostrider]

How much is it going to cost?

Probably about the same as their current chips -- a little more right at release.

Whoa, 45 nm! I remember when Intel released the Prescott 90nm CPU and ditched the 130nm Northwood -- Prescott required more power than Northwood and also a MUCH longer pipeline (31 stages instead of 20!) and longer latencies...what a waste.

Both are about the same, the Prescott had 2x the L2 cache of the Northwood (1 MB vs. 512k) as well as SSE3. The extra L2 cache should offset the longer pipeline. Tom's hardware reported that two 3.2 GHz Northwood vs. Prescott CPUs performed about the same across several benchmarks. The benefit is of course that the Prescott die is smaller due to the process technology change so of course more die / wafer = more $.

Now that AMD and Intel have both gone dual core, I hope Intel can learn to keep their temps under control. I don't like my electricity bill to make me go broke.

Intel will become the energy efficiency leader for high-end performance CPUs. The Core2's are 65 Watt parts (maximum) and have features built into the CPU to reduce power consumption further -- basically idle parts of the CPU when it is not under full load. AMD has some 65 Watt parts, but the key is that Intel is almost a full process technology ahead of AMD. AMD just started shipping 65 nm last month and Intel has already booted their first 45 nm CPU. AMD does have an interesting idea with their 4x4 platform which is supposed to become 8x8 next year (although it actually uses dual and quad core CPUs, not a single 8-core CPU) and the reviews of it so far do not look that promising. I remember reading one review on the 4x4 that recommended a 1 kW power supply. Since when does my PC need more power than my microwave? I still say Intel's greatest chip was the mighty Pentium Pro. It's not that fast today, but it came right during the Internet boom (when the average user could actually appreciate the full speed of the CPU) and it was one badass CPU for its time. It was revolutionary too, the first CPU with it's L2 cache on processor that ran at processor speed. The P2 was actually a step-back when it was later released in that the L2 cache on that CPU only ran at 1/2 CPU speed. Although the CPU was huge and looks good on my desk. Intel has released many processors which initially were a step back from what was already on the market -- Pentium 60/66 Mhz -- some 486's were faster, first Pentium 4's (some Pentium 3's were faster).

[doug123]

Hey, I'm so out of date with my CPU knowledge.

I used to visit Anandtech.com, Tom's Hardware, HARDOCP.com -- on a daily basis. Give me some time to catch up. The last time I was obsessed with computer hardware was Spring 2004.

I did a bit of research and decided to make a move to buy an Athlon64 X2 2.2 GHz dual core around the beginning of this year. That was when AMD was leading; now it looks like Intel's in charge. It's ironic running a 64 bit chip when there's no practical OS to support it. Vista looks like it's coming soon. I try to reinstall XP at least every 6 months; I keep a 12 GB partition just for XP as SP2 made the install much larger.

My favorite computer freak website is still Tweakhound.com..

Check out this:The TweakHound XP Page. Bad ass!

I also like TweakHound's Super XP Tweaking Guide

[Ghostrider]

tomshardware.com and hardocp.com all the way

[Matt]

I've not really taken much noice of computer hardware advances these days too... before I used to track a lot of computer technology advances but haven't had much time lately. Looks like things are moving along nicely though

[stephenszpak]

http://www.youmightb...mputergeek.html

I guess I better add that I'm just kidding here.
(hope you all assumed that already)

-Stephen

Edited by stephenszpak, 21 January 2007 - 04:55 AM.

[Ghostrider]

Equally amazing as this stuff is how fast graphics cards have developed in the past few years. They are starting to invade space previously reserved only for the CPU. Good stuff.

Can we get rid of the flood control? 180 seconds is too long to wait.