Last Passing Maneuver: Tualatin 1266 With 512 KB Versus Athlon And P4 – THG.RU

Tualatin – Shadow Boxer

On the left, Coppermine in FCPGA version, on the right, Tualatin in a FCPGA2 housing with a metal integrated heat spreader (IHS).

The Pentium III has been dropped from Intel’s marketing campaigns. With renewed confidence, the processor giant is concentrating on Pentium 4. But everyone missed it when the onetime problem child, the 1.13-GHz Pentium III, was completely overhauled. The change in process technology from 0.18 to 0.13 microns not only allows power consumption to be reduced considerably, it also smoothes the way to higher clocking rates.

The old Coppermine core has left the building, while the Pentium III with the Tualatin core has turned up on the market without any great fanfare. There’s even something additionally special about it: instead of the usual L2 cache size of 256 KB, variations with 512 KB are now available. Those are the ones that got our attention. We test the Pentium III 1.26 GHz-S with the 512 KB L2 cache and get extraordinarily high performance rates.

From PIII to PIII: Upgrade With Obstacles

Socket 370 on an i815 motherboard for PIII Coppermine or PIII Tualatin.

Just like the old Coppermine, the Pentium III Tualatin fits into a socket 370. No changes are needed from a purely mechanical point of view. Although Intel lists the Tualatin as a “normal” Pentium III on its Web site – after all, it does run with the i815/Solano chipset – the devil is in the details. The truth only emerges when you study the specification updates and white papers: in three important areas, changes are necessary.

10 New Pins

On the left, the PIII Coppermine, on the right the PIII Tualatin: the 370 pins are a constant. Only the SMD components are smaller than the predecessor’s.

Intel already did it once when moving from the Celeron/Mendocino 533 (black PPGA case) to the Celeron/Coppermine 533A (green FCPGA case): new pins required modifications on motherboards. The Tualatin has pins that have been altered too. The pin count of the 370 has not been tinkered with, because that would have meant a new socket.

The chart below shows the pin IDs that were replaced by Intel. Unlike Coppermine, all others retain the same significance. The AF36 is one of the important pins. Its voltage functions to allow the chipset to recognize the processor type. If the AF36 has Vss voltage, then it is a PIII Coppermine; otherwise, it is a Tualatin that occupies socket 370. Depending on the condition, the FSB buffer mode on the i815 chipset and the appropriate Vtt voltage (1.5 or 1.25V) are set.

B-Stepping With The i815/Solano

At first glance it seems to the user as though the Tualatin were behaving like a classic Pentium III and thus making do with the same chipset. But this is only partly right. The Tualatin is completely unsuited to older socket-370 chipsets like the 440BX, the i810/Whitney or the i820/Camino. Not even a socket-to-socket adapter that would adapt the voltage or the pins accordingly would help. The main difference is the bus protocol that has been switched from AGTL+ to AGTL (AGTL = Assisted Gunning Transceiver Logic). The only chipset that Intel has revived is the i815/Solano. The necessary logic is included in what is known as B-Stepping.

The unpracticed eye will find it difficult to tell the difference between the old A2-stepping Solano and the new B0, because the imprint on the first two lines is identical. Only the fourth line will give you a clue. This number allows you to tell the version. We compiled this table for the two major versions of the 815 chipset, one with integrated graphics (82815-Northbridge) and the other without a graphic core (82815EP).

The S-spec is critical. You will find it on the fourth line of the Northbridge chipset.

SL4DF means that this chipset was manufactured according to the old A2 stepping process (see table above).

According to the table on the last page, the SL5NR conceals the new B0 stepping. This version is the right one for the PIII Tualatin.

VIA Is Clear: T Positioned In The Rear

The only VIA chipset altered for the Tualatin is the Apollo Pro 133A, which the manufacturer now marks with a “T” suffix. It can be clearly distinguished from its predecessors on the VT82C694T Northbridge.

Core Voltage Reduced

Changing the process technology from 0.18 to 0.13 microns not only reduces the surface of the die, it also makes it easier to decrease the Vcore core voltage. While the fastest Coppermine with 1.00 GHz needs 1.75V, the Pentium III-S 1.26 GHz (Tualatin) manages with 1.45V. That is how Intel lowers not only the power consumption but also the heat developing in the chip.

Pentium III – Now With Three Different Cores

While only one Coppermine version was produced for the old Pentium III, Intel approaches the Tualatin in a different way: It is available with a 256 or 512 KB L2 cache. It works at full processor speed with all models.

Motherboards: Hardly Different On The Outside

In spite of changes to the pin layout, smaller core voltages and reworked chipsets, the switch to the Tualatin was made easy for motherboard manufacturers. Hardly anything needs to be changed in the layout, because farsighted companies have already built in voltage regulators with a greater range. The chipset remains completely pin-compatible, regardless whether it is an Intel 815 or VIA Apollo Pro 133 (A or T). Only the circuits for the 10 new pins need to be correctly assigned — a simple step in practice.

Hardly any difference can be seen between this MSI board with 815EP chipset and its forerunner.

The manufacturer does the same thing with this variation of the VIA equivalent.

On the 815EP board, MSI marks the Tualatin support by adding T after the model number.

The VIA 694T Pro variation additionally gets a sticker for socket 370.

Test Setup

WCPUID From H-Oda

The WCPUID tool from H-Oda indicates a cache size of 512 KB for the Pentium III-S (Tualatin).

Benchmarks

In order to tell apart the two Pentium III models, we will call the old Coppermine “Cumine”, and the Tualatin (512 KB) with the same suffix. In order to compare the performance of the Tualatin 512 and the Coppermine 256 directly, we lowered the speed of the Tualatin to 1000 MHz. With the same clock speed on Coppermine and Tualatin, the difference between the 256 and 512 KB L2-cache becomes very clear.

The same thing is done with the Athlon. Here we are comparing the Tualatin 1200 with the Athlon 1200. For the sake of thoroughness, the results of the Pentium 4 1800 and the Athlon 1400 are also given.

Quake 3 Arena

At this lower (640 x 480) resolution, the bottleneck is not at the graphics card. It is worth noting that the Tualatin profits enormously from its 512 KB cache. At the same clock speed of 1000 MHz it is miles above its older brother, Coppermine. Even a comparison of Athlon and Tualatin 512 architecture reveals an important connection. At 1200 MHz, the Tualatin is just a tiny bit faster than the Athlon 1200. However, the Athlon can make up for this deficiency with a higher absolute clock speed. The Athlon 1400 is the top model available commercially, while Intel only offers a 1266 MHz maximum.

In commonly used 1024 x 768 resolution, the architecture of the graphics chip (and card) has a greater impact on overall performance. In this respect the Tualatin rivals even the Pentium 4, whereas the Athlon must take a back seat. No hasty conclusions will be drawn here. A conclusion will only be possible after we’ve gone through the following tests.

Unreal Tournament UTBench

In UTBench, the PIII Tualatin 1266 would have beaten almost everyone else. The Pentium 4 1800 has already been surpassed. The Athlon 1400 plans to give as good as it gets. Keep an eye on the 1400 MHz that Athlon has to pit against the Tualatin 1266!

The PIII Tualatin 1266 is ahead of the Pentium 4 1800 even at a resolution of 1024 x 768. The Tualatin 1200 is once again faster than the Athlon 1200.

Aquamark

With later-generation games like Aquamark, the greater complexity of the Triangle setup requires more computer power from the floating point unit (FPU). This is where the Athlon clearly has the superior architectural prerequisites.

At both resolutions, the P4 1800 takes the limelight: It is slightly above the Athlon 1400. In the Intel model, this is more likely owing to the higher clock speed than to superior architecture.

Sysmark 2000

In the conventional 2D performance gauge, Sysmark 2000, the Tualatin reaches excellent performance compared to its clock speed. In a direct comparison it trumps both the Coppermine (1000 MHz) and the Athlon (1200 MHz). The Athlon can only compensate for this disadvantage with a higher clock speed. Currently, the top model is available with 1400 MHz, while Intel limits itself to 1266 MHz.

Cinema 4D Ray Tracing

In ray tracing, the floating point performance of a CPU is more important than the cache size. Here the Athlon plays its trump card.

3D Mark 2000 and 2001

Not much can be drawn from these two charts. Here, synthetic benchmarks are at a serious disadvantage vis-a-vis real world applications. While the Tualatin leads in the 3D Mark 2000 …

… the Athlon looks like the victor in 3D Mark 2001. So be careful with this benchmark!

FlaskMPEG: Encoding According to MPEG-4

When converting MPEG-2/DVD movies into the space-saving MPEG-4 format, the Pentium 4 clearly rules. Even so, the Tualatin may oust the Athlon.

SiSoft Sandra: Synthetic, so beware!

MFLOPS/MIPS tests show that at 1000 MHz, the cache is less important in this category. The difference between the Tualatin 1000 and the Coppermine 1000 is not great.

SiSoft Sandra: Multimedia & Memory

SSE versus 3DNow. AMD only stands up to the others at higher clock speeds.

In memory performance, only the Pentium 4 has anything to brag about.

Conclusion

In a direct clock rate comparison (clock-by-clock), the Tualatin 512 KB has on its plus side considerable performance advantages in many categories over 256-KB CPUs like the Pentium III Coppermine, the Tualatin 256 KB or the Athlon. Except in floating point performance, where no one can hold a candle to the Athlon, the architecture of the PIII Tualatin would be quite attractive to the standard user. Moreover, the switch in the manufacturing process from 0.18 to 0.13 microns would enable significantly higher clock speeds than the feeble 1266 MHz.

But Intel’s priority is to avoid leaving its self-declared favorite, the “Pentium 4”, high and dry. In the face of policy-bound price distortions, many home users are keeping away from the Pentium III-S 1266 (512 KB). All other candidates, whether the Athlon or the “lesser” Pentium IIIs, offer definitively better cost effectiveness. And there’s more: Intel wants to stop at 1266 MHz! With the Tualatin’s 0.13 microns, Intel would not have had any problem instigating a fresh clock rate war with the Athlon (0.18 microns). But Intel won’t saw off the branch it is sitting on. The Pentium 4, whose architecture is designed for clock rates that are well under the 3-GHz brand, is the declared flagship for the future.

In the short run, Intel still makes upgrading a farce: because of altered pins and a new bus protocol, a new “Tualatin-compatible” motherboard must still be purchased despite having the same socket 370. The current situation makes the PIII Tualatin with 512 KB attractive only for certain server applications, especially if the procurement costs are less important.

One last thing to consider: only slight changes from the Coppermine were made to the architecture. Research and development costs have long since been recovered with the Pentium III. The return on investment was therefore realized a long time ago. Only the cache memory was increased. But you can do that simply by clicking into the right software library in the design department. The miniaturization to 0.13 microns even enables a higher yield rate. Although these would be good conditions for lower prices, Intel is playing the martyr with its Pentium III-S 1.26 GHz. It’s still a mystery to us why Intel even put this CPU on the market.