IBM's first dual-core G5-class processor will be the PowerPC 976. It will also be the first PowerPC fabbed using a 65nm process.
So claims web site TeamXbox following up on a San Jose Mercury story presenting leaked Xbox 2 specifications.
The Xbox-oriented site cites a variety of unnamed sources as the basis for its information. Said sources allege that the 976 will be based on IBM's Power 5 architecture, including the latter's simultaneous multi-threading facility - the same basic technology as Intel's HyperThreading - which allows it to process two program threads at once.
The sites information, however, is at odds with details we received a little while back that purports to show IBM's 64-bit PowerPC roadmap. Dated December 2003, the roadmap calls the first Power 5-based PowerPC the 980, and has it fabbed at 90nm, not 65nm. The first 65nm chip is the 990, allegedly based on the undoubtedly upcoming Power 6 architecture.
That said, the first dual-core PowerPC is based on Power 5 and fabbed at 65nm. However, it's down as the 9800, a name, like that of the 980 and 990, that have been cropping up on the rumour mill since early last year.
The roadmap certainly looks like an official IBM document, but we note that the PDF we were sent was not generated by the software IBM usually uses for such work. It also uses the word "HyperThreading" to indicate the use of simultaneous multi-threading technology, and we find it hard to imagine IBM using an Intel trademark with one of its own CPUs, even on an internal roadmap.
In short, the roadmap looks a little too much like a PowerPC fan's wish-fulfilment, and we're sceptical of its provenance.
We're keeping an open mind on the TeamXbox data too, since we'd expect a version of the 64-bit PowerPC based on a more advanced architecture - ie. the Power 5 - to have a name that more clearly distinguishes it from the 970 series.
At 65nm, the chip isn't likely to appear until late 2005 or early 2006 at the soonest, so the name should perhaps be considered provisional.
However, with both Intel and AMD developing multi-core chips for their 65nm node product lines, it seems unlikely that IBM would miss this trick too.
TeamXbox gives no clock frequency data, but the so-called roadmap suggests speeds of 4.5GHz and up. Again, that sounds a little too good to be true. ®