Ever since AMD’s Thunderbird/Duron release in June, the CPU industry has been pretty quiet.  There has been a lot of talk going around about memory technologies and chipsets, but as far as the processor clock speed race is concerned, things are not nearly as bad as they were leading up to the release of the first 1GHz chips from AMD and Intel. 

AMD’s Thunderbird helped to narrow the performance delta that existed between the Athlons and the competing Pentium IIIs, thus placing more pressure on Intel to do something to regain either the performance or the clock speed advantage. 

Towards the end of June, after AMD’s barrage of processor announcements and releases, Intel did attempt to steal the lime light for a bit by announcing that a faster Pentium III was on its way, once again, in “limited quantities.”

That time is now and the “faster” Pentium III happens to come clocked at 1133MHz, or 1.13GHz for short. 

CPU Specification Comparison
	AMD Athlon			Intel Pentium III		Intel Celeron
Core	K7	K75	Thunderbird	Katmai	Coppermine	Mendocino	Coppermine128
Clock Speed	500 - 700 MHz	750 - 1000 MHz		450 - 600 MHz	500 - 1133 MHz	300 - 533 MHz	533 - 600 MHz
L1 Cache	128KB			32KB
L2 Cache	512KB		256KB	512KB	256KB	128KB
L2 Cache speed	1/2 core	2/5 or 1/3 core	core clock	1/2 core	core clock
L2 Cache bus	64-bit				256-bit	64-bit	256-bit
System Bus	100 MHz DDR (200 MHz effective) EV6			100 - 133 MHz GTL+		66 MHz GTL+
Interface	Slot-A		Socket-A Slot-A (OEM only)	Slot-1	Slot-1 Socket-370		Socket-370
Manufacturing Process	0.25 micron	0.18 micron		0.25 micron	0.18 micron	0.25 micron	0.18 micron
Die Size	184 mm^2	102mm^2	120mm^2	128mm^2	106mm^2	153mm^2	106mm^2
Transistor Count	22 million		37 million	9.5 million	28 million	19 million	28 million

The Chip

The new 1.13GHz chip does very little to set itself apart from the rest of the Pentium III line, simply because it is still a member of the same family the only difference being its higher clock multiplier and its resulting increase in clock speed. 

• 28 million transistor 0.18-micron Coppermine core
• 1GHz clock speed – 8.5x clock multiplier
• 32KB on-die L1 cache running at core speed
• 256-bit Advanced Transfer Cache - 256KB on-die L2 cache running at core speed
• Advanced System Buffering
• 242-pin Slot-1 GTL+ CPU interface running at 133MHz
• 1.75v core voltage

The 1.13GHz Pentium III is no different than the original Coppermine based Pentium III that was released in October 1999, but as usual there is one notable exception. 

Intel has increased the core voltage of the Pentium III yet again, this time up to 1.75v in order to hit the 1.13GHz mark.  If you remember the Pentium III needed a bump up to 1.70v in order to hit 933MHz as well as the 1GHz mark, this was a 3% increase in voltage over the original 1.65v specification and now the core gets another 3% increase in order to hit 1.13GHz. 

Most overclockers are already familiar with what Intel is doing here, they’re simply increasing the core voltage on the Pentium III in order to get higher yields on the CPUs.  Of course when Intel or AMD do it they’re “increasing yield” but to us it’s commonly known as overclocking ;)

Regardless, the 1.75v core voltage setting of the new 1.13GHz is within the operating limits of the Pentium III core so there’s nothing to worry about in terms of reliability.

Just like the Pentium III 850/100, the 1.13GHz chip makes use of the 8.5x clock multiplier combined with the 133MHz FSB in order to hit the 1133MHz mark.  In order to support the 8.5x clock multiplier Intel remapped the 4.5x clock multiplier on the Pentium III 850 & the new 1.13GHz CPUs to the 8.5x setting so don’t worry if your motherboard doesn’t have an 8.5x multiplier setting.  Also, since all Intel CPUs are multiplier-locked, your motherboard only really needs to have support for the CPU itself with the ability to correctly identify it, the processor will use the clock multiplier it needs.  

The 1.13GHz part is another big sign from Intel that we’re not going to be seeing any more 100MHz FSB Pentium IIIs, leaving the fastest 100MHz FSB Pentium III at 850MHz. 

Currently, the 1.13GHz Pentium III will be available as a Slot-1 processor only but it shouldn’t be long before the 1.13GHz parts make their way into a FC-PGA 370 package.

If you’re not familiar with some of the features the Coppermine core offers, the two biggest and most talked about benefits of this core are the Advanced Transfer Cache (ATC) and the Advanced System Buffering (ATB). 

The ATC on the Pentium III is just the fancy name for the on-die 256KB L2 cache.  Now keep in mind that the Pentium III isn’t just a Celeron with twice as much cache and SSE, the L2 cache bus has been increased from the 64-bit bus width on the older Pentium III and Celeron processors to 256-bits wide.  The ATC also refers to the 8-way associativity of the 256KB L2 cache on the Coppermine (compared to the 4-way associative L2 cache on the old Pentium III/Celeron). 

Because the 256KB of L2 cache is on-die, the transistor count of the Pentium III is increased tremendously over the 9.5 million transistors that made up the original Pentium III (Katmai) core.  The 256KB L2 adds about 19 to 20 million transistors, putting the total transistor count of the Coppermine at approximately 29 million transistors. 

Advanced System Buffering is a simple term that represents the increase in buffers the Pentium III Coppermine offers over the previous generation of processors, including the Katmai based Pentium IIIs.  If you are interested in specifics there are now 6 fill buffers, 8 bus queue entries and 4 writeback buffers (up from 4, 4, and 1 respectively).  These three optimizations all help to take advantage of the 1.06GB/s bandwidth offered by the 133MHz FSB. 

Cooling the Chip

The first thing that we noticed when the 1GHz CPUs came in from AMD and Intel was the size of the heatsinks that were present on the CPUs.  The 1.13GHz Pentium III makes use of an ever bigger heatsink and for the first time, the retail boxed heatsink/fan combo makes use of two fans as you’ll see in the pictures below.

This is the heatsink our 1GHz Pentium III came outfitted with:

Click to Enlarge

Test Notes

• Since the 1.13GHz Pentium III is only available in a Slot-1 form factor we weren't able to run any i815 tests on the CPU as all of the i815 boards we have in the lab are all Socket-370.

• The overclocked 1.1GHz Thunderbird would not run reliably enough under Windows 2000 to obtain any benchmark numbers from. Thus all 1.1GHz Thunderbird scores are available under Windows 98SE only.

The Test

The increased clock speed of the Pentium III 1.13GHz propelled it to the top of our SYSMark benchmark chart and when combined with the BX chipset overclocked to 133MHz you get a combination that ends up being incredibly fast. The overclocked Thunderbird running at 1.1GHz comes close but doesn't quite surpass the Pentium III, we should be seeing AMD's 1.1GHz Thunderbird hitting the streets relatively soon as well but for now we can only overclock it to get above the 1GHz mark.

The Pentium III has always been a favorite of Quake III Arena, and for those of you that are Quake III Arena fanatics (we can't blame you, RA3 is quite addicting) you'll be impressed to see a close to 200 fps score brought courtesy of the overclocked BX platform and the Pentium III 1.13GHz processor.

While something like this isn't very realistic for your average gamer since the processor would set you back a considerable amount of cash, it's always nice to look at the performance the higher end chips can offer since in a few months time these speeds will become mainstream.

The beauty of this test is to illustrate that you don't need a 1.13GHz chip to deliver high frame rates in games if you have a powerful enough video card, such as the GeForce2 GTS we used as our test video card. The < 1 fps variation in performance of the top 10 CPUs is entirely normal variation in frame rates and doesn't really mean anything about the performance of a particular processor. What it does say is that you can definitely "get by" with a 600MHz CPU and a powerful video card if your main interest is gaming.

UnrealTournament provides us with a very good CPU benchmark as the performance scales quite well with CPU speed. The standings are pretty much identical to Quake III Arena, illustrating that a fast CPU will give you more than just good performance under a particular title.

It seems like picking a CPU is much easier than picking a video card ;)

As fill rate/memory bandwidth limitations of the GeForce2 GTS begin to kick in, the performance of the various platforms decreases but the standings generally remain the same.

Expendable tells the same story we've seen thus far, although this time the overclocked 1.1GHz Thunderbird comes very close to the performance of the 1.13GHz Pentium III on an overclocked BX133 platform which is very impressive.

In spite of Content Creation 2000's multitasking nature, other limitations such as system memory bandwidth, FSB bottlenecks, etc.. kick in thus limiting the improvement another 133MHz offers over the previous 1GHz processors. For business applications and the less demanding content creation applications, even a Pentium III/Thunderbird 1GHz is overkill. Any of the CPUs on the above chart would perform just fine in either of those situations.

High End Winstone 99 still goes to the Pentium III 1.13GHz with the Thunderbird coming in second place. It's interesting that the VIA 133A platform is very competitive with the overclocked BX133 setup in this benchmark.

The Quake III Arena benchmarks under Windows 2000 very closely mimic those we provided under Windows 98SE with the exception that there is a bit of a performance increase courtesy of 2000's robust nature.

Once again, you don't need to have the fastest CPU to get the highest frame rates in Quake III Arena, you're often times going to be limited by your video card before your CPU if you have a decently fast processor.

SPECviewperf has always been an Athlon fan, and even the overclocked BX platform running the 1.13GHz Pentium III can't outpace a 1GHz Thunderbird. For the most bang for your buck in professional level OpenGL applications, it seems like the AMD Duron with a fast enough graphics card (GeForce/GeForce2 GTS) should do just fine.

The DesignReview viewset tilts the balance in favor of the Pentium III as the top two clock speeds take the winning two positions, both of which happen to be on overclocked BX platforms as well.

This time the performance title goes back to AMD's side with the Athlon and the newer Thunderbird, there seems to be virtually no difference between the older K75 Athlons and the newer Thunderbirds in this test illustrating that cache size/frequency doesn't seem to matter that much here, the Athlon's 128KB L1 seems to be doing the trick.

AMD takes the lead once again with the 1.13GHz Pentium III following close behind the Athlon 900.

The RC5 benchmark once again proves that L2 cache frequency and memory bandwidth doesn't matter in situations like this, rather clock speed and raw CPU performance. For more information about RC5 and how you can join AnandTech's RC5 team click here.

For now the fact remains that if you happen to have a BX motherboard that supports Coppermine CPUs, you're probably better off sticking with your current platform and possibly overclocking it to make use of the 133MHz FSB.

The VIA Apollo Pro 133A platform is finally at the point where it can be considered to be quite mature, there are obviously some quirks about the platform (chipset patches, GART drivers, etc...) that you have to deal with but it's nothing that your average hardware enthusiast can't tackle. For a comparison of the best 133A boards out there, visit our most recent Apollo Pro 133A motherboard roundup.

For those of you that want to stick to an Intel chipset but still get PC133/133MHz FSB support, the i815 is a great option and pairs up with the Pentium III quite well, the only downside is that because of its integrated video the boards that are currently available are carrying pretty hefty price tags, most of which are currently retailing for above $150.