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.