Intel Pentium III 1.2GHz 0.13-micron Tualatin: The Celeron of the Futureby Anand Lal Shimpi on July 30, 2001 3:30 AM EST
- Posted in
More than just a die shrink
The 0.13-micron Pentium III has specs that are virtually identical to the 0.18-micron
On the compatibility side, the Tualatin requires a new chipset because of its use of a lower voltage clocking specification. Since the release of the Pentium Pro, all Intel P6 processors have used Gunning Transceiver Logic+ (GTL+) technology for their FSB. The GTL+ implementation actually changed slightly from the Pentium Pro to the Pentium II/III, and thus the latter implement what is known as the Assisted Gunning Transceiver Logic+ (AGTL+) bus. Both of these FSBs use 1.5V signaling; however, the Tualatin uses a lower voltage bus that runs at 1.25V. More specifically, the Tualatin uses AGTL signaling that unfortunately requires a new chipset with support for 1.25V AGTL signaling instead of 1.5V AGTL+ signaling. The Tualatin also supports single-ended and differential bus clocking schemes (whereas the Coppermine Pentium III only used single-ended clocking). It is unclear whether the current 1.13GHz and 1.2GHz Tualatins use single-ended or differential clocking, but the main purpose for using a differential bus clocking scheme is to reduce Electromagnetic Interference (EMI) associated with higher clock speeds. The Pentium 4 also uses differential clocking.
Because it is manufactured on a smaller process, the Tualatin requires much
less power than the
In terms of performance, the Tualatin offers one advantage over the
Unfortunately, the Tualatin’s DPL is not as useful as similar functions in the Athlon 4 and Pentium 4 because the Tualatin is still stuck with only a 133MHz FSB. The 64-bit AGTL FSB is only capable of a peak theoretical maximum of 1.06GB/s of bandwidth, while the Athlon 4 and Pentium 4 have 2.1GB/s and 3.2GB/s of FSB bandwidth, respectively. The effectiveness of the Tualatin’s DPL is thus reduced because it does not have as much FSB bandwidth, but that also means that at higher overclocked FSB frequencies, the Tualatin will benefit much more than the Coppermine Pentium III did.
Other than those two changes, the desktop Tualatin-based Pentium III carries
an identical feature set to the