Comparing Intel's and AMD's (almost) Finest
I’m sure this will be the first of a series of comparisons between the Intel Pentium 4 and the AMD Athlon based systems that I write over the next few months. I plan on updating it from time to time as revisions and new models of both the CPU’s and chipsets are released, but let’s just focus on what is available now to get a peek at what is to come. I had planned on waiting a bit for this series of articles but I think it may be interesting to watch the performance changes as the products progress over the next few months.
The recently introduced Intel Pentium 4 2.0GHz is currently the fastest in the Intel CPU line, while the AMD Athlon is currently available in speeds up to1.4GHz with the Thunderbird core for desktop CPU’s. The Athlon MP for multiprocessor applications is available at 1.2GHz, and it has the new Palomino core. However, AMD will be releasing the desktop Athlon with the new Palomino core in speeds up to 1.5GHz in the next three to five weeks, so which to compare with? I started out thinking of using an Athlon 1.4 (T-Bird), but decided against it because of the impending release of the Palomino core for the desktop (one of the reasons I’d been waiting to run these tests). So I decided to use an Athlon MP 1.2 as a single CPU for the test, figuring I would compare it to the P4 running at about 1.7~1.8GHz on a i845 SDRAM based Mainboard. Why the i845? Well, my rationale was that since AMD CPU’s cost less, it would make sense to compare using the lower priced i845 and SDRAM combination over a more expensive i850 and RDRAM setup. Some may say I should have considered an SDRAM Socket A chipset such as the KT133A instead of the DDR KT266, but since the DDR Mainboards are more current (just like the Intel platforms) I felt it was appropriate to use the KT266 and DDR. My goof was thinking I should be comparing the SDRAM based i845 to the Athlon at all!
When released, the Palomino core Athlon should start at 1.3GHz and go through 1.5GHz initially, topping the current max speed of 1.4GHz for the T-Bird Athlon. Since it only made sense to compare the latest P4 to what will be the latest Athlon, my only issue now was that the Athlon MP is currently only rated for 1.2GHz, while the P4 goes all the way to 2.0GHz. So I started out trying to find a speed range for the P4 that would be about equal in performance to the Athlon MP at 1.2GHz. I knew 1.5GHz for the P4 was too low so I tried 1.7,but that was also too low. I then tried 1.8GHz, but that was still too low! So I said the heck with it and used 2.0GHz. This also allowed me to compare both the Intel 845 SDRAM and 850 RDRAM chipsets, something I had not planned on doing initially. I had planned to just use the i845, since I can set the Soyo P4ISR to any multiplier I wish, but now that I was going to use 2.0GHz I could also compare using the D850MD RDRAM 850 chipset based Mainboard. It turns out that was a good thing to do.
I decided to use a Soyo K7V Dragon using the VIA KT266 DDR SDRAM chipset, but that brought up another issue, as the KT266 will be replaced shortly with the KT266A, which should have better performance. Well, like I said this article is only the first in what may be a long series.
So what did we end up with? Comparing the state of the art Intel Pentium 4 2.0GHz CPU (by that I mean the latest and fastest) with the latest i850 (high end in price and performance) and the i845 (midrange in price and performance) chipsets to a 1.2GHz Athlon MP CPU that runs at a slower speed than the soon-to-be-released desktop version, with chipset that has worse performance than the soon-to-be-released replacement. Doesn’t seem fair to the AMD does it? Well let’s find out.
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AMD's Athlon 64 CPUs
AMD has been promoting their K8 CPU, better known as the Hammer series, for well over a year now. These desktop parts were postponed for about ten months while AMD's strategy changed a bit and began to focus on their Opteron server-class CPUs. Today, AMD is announcing their Athlon 64 3200+ CPU and their Athlon 64 FX 51. From this point on, we will refer to them as the Athlon64 and the AthlonFX to avoid confusion.
The "64" in their name comes from the ability of these new CPUs to run the AMD64 instruction set that will be supported by the upcoming Windows XP 64-Bit Edition operating system. Moving to a 64-bit operating system with a 64-bit CPU will have some obvious advantages, although it's clear that you will not be seeing many of them right away. A 64-bit computing experience means that our PCs will no longer be limited to addressing only 4GB of RAM. In a 64-bit environment, it's now possible to address 8 terabytes of memory. In order to make the Athlon64 CPUs 64-bit compliant, the appropriate registers have to be added to the CPU. This has only increased the die size of the processor by 1 to 2%. Going to 64-bit has actually not been that costly from the standpoint of physical implementation.
The real beauty here lies in the Athlon64's ability to run current 32-bit applications and operating systems right now, and with "no" penalty. When 64-bit applications and OSes come to market, the Athlon64 will be ready to take advantage of them and still be able to run native 32-bit apps right alongside the 64-bit ones. Of course, we're focusing on Windows operating systems, as they are by far the majority of the desktop market. From what we've seen, current 32-bit applications run just as well on the new 64-bit OS from Microsoft. Some run a bit slower, some run a bit faster, but overall it's pretty much the same. Most likely no tangible performance differences will ever be noticed. These new processors include a wide range of specialized instruction sets besides the 64-bit expansion, including AMD64, MMX, 3DNow!, SSE, and now SSE2.
Both of the new Athlon64 CPUs will utilize HyperTransport technology. They will have available one HyperTransport link that is 16-bits wide and can move 3.2GB/s of data in each direction simultaneously. This link is used to communicate with the northbridge controllers. Obviously this gives a large amount of bandwidth to the CPU to work with other devices on the mainboard. Currently the AMD Athlon 64 FX and Athlon 64 can communicate with the chipset at speeds of up to 1600MHz. Keep in mind that "up to" does not mean "always", as we will show later.
The memory controller is no longer on the northbridge chipset. Instead, AMD has taken control of this aspect of the system and has integrated the controller onto the CPU die itself. Latency has been reduced significantly due to this, so this certainly comes as a very welcome change. Because the memory controller is located on the processor die, the memory subsystem traffic no longer has to go through the chipset for CPU-to-memory calls. Hence, the old term "front-side bus" isn't really applicable any longer. With AMD64 processors, the speed at which the CPU and memory controller interface is at full processor frequency.
AMD Athlon 64 FX 51
This is currently AMD's flagship processor. Gone is the performance rating, though we do get a little more marketing. The CPU we tested was supplied by AMD. The "FX" and "51" are ambiguous at best, meaning nothing beyond the overused FX cliché. 51 is the model number, which will scale with newer processors. The next CPU will likely be a model 53, with the 53 obviously being faster than the 51.
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The packaging is a 940-pin lidded ceramic micro PGA. The lidded portion refers to the big metal heatspreader on top of the CPU, which is certainly a welcomed addition. This part runs at a 2.2GHz (11 x 200 CPU Clock) clock speed and supports Dual 64-bit DDR memory channels, which provides a 128-bit wide memory bus and 6.4GB/s of bandwidth working at DDR400 specifications. Fallback to DDR200 is supported. This AthlonFX will require the use of registered DIMMs. Remember that the memory controllers on the K8 are now on-die and fully in the control of AMD, not the chipset builders.
Many of you might be looking at this CPU and asking, "Isn't that an Opteron?" and you would be close to right. The AthlonFX is very much an Opteron in desktop clothing, right down to the pin count. The differences are that the Opteron is not specified to run DDR400, only DDR333, and officially two of the HyperTransport bus interfaces have been removed from the AthlonFX.
AMD Athlon 64 3200+
This will pan out to be AMD's mid-level CPU. It still carries a performance rating and picks up where the AthlonXP left off with the "3200+" moniker. It should be noted that AMD would not supply a sample of this CPU to be tested. Our connections in Taiwan supplied samples for testing.
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The packaging is a 754-pin lidded organic micro PGA. Again, we see the heatspreader. This part runs at a 2.0GHz (10 x 200 CPU Clock) clock speed and supports an integrated single 64-bit DDR memory channel providing 3.2GB/s of bandwidth working up to DDR400 specifications. It also has fallback to DDR200 as well.
AthlonFX and Athlon64 Similarities
Basically what you have seen listed above are the differences in our two new CPUs from AMD. Instead of writing everything twice, we've decided to give you a list of specifications that are shared between the two parts.
L1 Cache Size: 128KB L1 (64KB instruction + 64KB data)
L2 Cache Size: 1MB L2 (exclusive)
HyperTransport Links: Supports single link - 6.4GB/sec per link I/O bandwidth
Fab location: AMD's Fab 30 wafer fabrication facility in Dresden, Germany
Process Technology: 0.13 micron SOI (silicon-on-insulator) technology
Die Size: 193mm2
Transistor count: Approximately 105.9 million
Nominal Voltage: 1.50v
Certainly what stands out here is the massive L1 and L2 cache sizes that are packed onto the AthlonFX and Athlon64. Also, the die size might jump out at you as being massive as well. Certainly these are not inexpensive CPUs to build. We do see a reduction in voltage, which will be welcomed by the enthusiast.
There is an on-die thermal diode that will allow the die temperature to be monitored when used with the proper software. This diode will also be utilized to shut down the CPU clock if there is a point where the die becomes too hot. The Athlon64 CPUs are specified to work from -55°C to 85°C. So, in short, we shouldn't see any more burned up AMD CPUs.
To drive the point home even more on just how alike these two CPUs are, take a look at their block diagrams side by side. The memory interface is truly the only difference.
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AthlonFX / Athlon64 and AthlonXP Differences
This chart will lay out all of the changes from the current AthlonXP. Besides the obvious interface differences that have been discussed above, the transistor count stands out like a sore thumb. The transistor count, having nearly doubled, can easily be blamed on the on-die L1 and L2 cache increases. Those caches have basically doubled from the XP to the Athlon64 as well as the transistor count and size of the die.
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There has been a lot of talk about the K8 core, but AMD has spent very little time marketing the actual advancements of the CPU pipeline. Here is the official word from AMD:
Processor core clock-for-clock improvements, including larger TLB (Translation Look-Aside Buffers) with reduced latencies and improved branch prediction through four times the number of bimodal counters in the global history counter, as compared to seventh-generation processors. These features drive improvements to the IPC, by delivering a more efficient pipeline for CPU intensive applications. CPU-intensive games like Comanche 4 and Unreal Tournament benefit from these core improvements.
The benchmarks will surely show us the truth here.
Athlon64 & AthlonFX in Action
Below we have screenshots of how the CPUs look in action. Notice the expanded L2 cache. Do note that the AthlonFX is not running at stock clock in our screencap.
More Info : http://www.hardocp.com/article.html?art=NTI0
or
http://www.realworldtech.com/page.cfm?ArticleID=RWT092601023506
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Pentium 4 vs. Athlon DDR
Grudge match above 1GHz
THERE'S NO LOVE LOST between the Intel and AMD camps these days. Both sides know they're in for the fight of their lives, and both are bringing spectacular advances to the desktop PC market with regularity. The latest salvos in the desktop wars are a whole new microarchitecture from Intel and a revamped Athlon platform from AMD. If you've not had the chance to do so yet, read up on these technologies in our review of the AMD 760 chipset with DDR SDRAM and our Pentium 4 review. We've already painted much of the backdrop for this article, and now it's time for the main event: The P4 and Athlon DDR in a head-to-head, take-no-prisoners benchmark brawl.
We've rounded up a 1.5GHz P4 system from Intel and tossed it into the ring with a 1.2GHz DDR system from AMD. To test our contenders' mettle, we've run them through a grueling gauntlet of benchmarks, from the highly synthetic to in-the-mud, real-world application tests.
Before the opening bell sounds, let's review our contenders' qualifications.
The Pentium 4's advantages
The Pentium 4 has been endowed by Intel with a number of natural advantages, not least of which is its incredible ability to ramp clock frequencies and, hand-in-hand with it, a hair-raising 1.5GHz top clock speed. Impressive as the GHz numbers are, though, the real story with the P4 is its ability to move data around inside the system. From the front-side bus to its RDRAM memory interface to its north-south bridge link, the P4 has a considerable advantage over the Athlon platform, at least on paper.
Let me slow down and run some of the numbers by you. The P4 has a 100MHz, "quad-pumped" front-side bus between itself and the rest of the system. To confuse you, we will, as always, refer to this bus interchangeably as 100MHz and 400MHz—whatever suits our purposes. This 400MHz monster can pump through up to 3.2GB of data per second. Coupled nicely with that bus are the P4's dual channels of PC800 Rambus DRAM, which can also push through 3.2GB of data per second at peak. Further down, in the less-exotic bowels of the system, the Intel 850 chipset has a 266MHz "hub"-style link between its north and south bridge chips. (Though Intel doesn't use directional terminology, the chips' purposes are basically the same as in most other contemporary PCs.)
In every one of these cases, the P4 has a system bandwidth advantage over the Athlon. If nothing else, the Pentium 4 platform has plenty of room to grow. And it ought to deliver a serious whuppin' at memory-intensive tasks.
The Athlon's advantages
Meanwhile, the Athlon's great advantage over the Pentium 4 is, well, the Athlon chip itself. AMD has created a wondrous thing in this processor, a marvel of x86-compatible design. Athlons have already easily outpaced the PIII in the megahertz race, and they're at least as fast, clock for clock, as any PIII chip. The Pentium 4 may run at higher clock speeds, but it does so by virtue of a very long instruction pipeline. The length of that pipeline hampers the P4's clock-for-clock performance, so that a 1.5GHz Pentium 4 isn't necessarily any faster than, say, a 1GHz Pentium III.
But then many things aren't as they seem once the theoretical performance numbers start flying around. For instance, the Pentium 4 talks to its L2 cache over a 256-bit wide connection, while the Athlon's L2 cache interface is only 64-bits wide. However, the Athlon Thunderbird's dual-ported, on-chip cache is probably just as good as the P4's.
But I digress. The advantages for the Athlon here include excellent clock-for-clock performance, especially in floating-point math, where the P4 is relatively weak and the Athlon is quite strong.
To bolster the Athlon's already strong performance, AMD has introduced a pair of platform enhancements. There's a new front-side bus speed of 266MHz, up from 200MHz. And there's the 760 chipset's ability to address double date rate (DDR) SDRAM. Created to combat the high prices (and latencies) of RDRAM, the DDR vs. Rambus struggle is a running subtext of the AMD-Intel conflict. The 133MHz variety of DDR memory, dubbed PC2100, can push through 2.1GB/sec, at peak—not as much as the P4's dual RDRAM channels, but twice the speed of conventional PC133 SDRAM.
In short, even though the Athlon is running at a clock rate 300MHz lower than the P4's, we're expecting big things out of this 1.2GHz DDR test rig.
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Not long after AMD claimed the title of the “world’s best processors”, four days to be exact, Intel is fighting back with all the Moore’s Law and Israeli-scientists it’s got, and today it launched the fastest quad-core consumer processor on the market, the Core 2 Extreme processor QX6800.
SANTA CLARA, Calif., Apr. 9, 2007 – Intel Corporation today advanced its enthusiast-level quad-core processor family with the introduction of the Intel® Core⢠2 Extreme processor QX6800, the company’s twelfth quad-core processor offering. Running at 2.93 GHz — the fastest native clock speed yet reached with the Intel® Core⢠microarchitecture for the quad-core desktop — this addition to Intel’s innovative processor family sets new standards for desktop PC performance. The Intel Core 2 Extreme processor QX6800 is ideal for those gamers, digital design professionals and enthusiasts who crave the highest performing computers they can get their hands on.
The Intel Core 2 Extreme processor QX6800 is produced on Intel’s industry-leading 65 nanometer process, key to enabling the large 8 megabyte cache. A 1066 MHz system bus is supported and the processor is available now at a cost of $1,199.
Of course, I don’t have one of these precious babies for testing to tell you exactly how awesome they are *cough*, so I’ll just have to base my analysis on this carefully crafted PR release. It’s this <--------------------> awesome!
One of the key benefits Intel describes as a result of increased performance is “better gameplay with more intelligent computer-generated opponents”. But I’ve always played computer games because I can actually win, and laugh at the stupidity of artificial intelligence. Does that mean I should stick to my slower AMD Athlon for dumber AI? The Intel spokesperson did not wish to comment.
A local bank has also informed me they will be be launching their new “Core 2 Extreme” loan alongside their “Playstation 3″ loan to accommodate the modern day geek. An anonymous bank staff tells me they’re appalled at the price of the Wii and AMD processors for undercutting profitability.
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Considering performance:
http://www.tomshardware.com/cpu/20050603/index.html