IBM Corp is beginning to attract criticism over the way PowerPC has fallen behind all the other major RISC families, Sparc, R- series, Precision Architecture and Alpha, in particular for the fact that an off-the-shelf 64-bit part is still a pipe dream – but all that is about to change if MacWeek Online is to be believed. Trouble is, there is still no sign of a 64-bit part, and although the roster is to include the first entry in the next-generation G3 series, they appear to offer little in the way of serious advances, and to be little more than a tardy effort on the part of the PowerPC partners to play catch-up. This first G3 part, code-named Arthur, is expected in late spring, and should be clocked at about 300MHz. The core architecture is expected to resemble the PowerPC 603e – that is of course the cleaned-up version of the original 601, but the addition of an on-board Level 2 cache controller and dedicated interface should take performance closer to the PowerPC 604e in some applications. Cache will initially be external, but a version with built-in cache is expected to ship in the autumn, but the part is not expected to provide any support for symmetric multiprocessing. In the 604e camp, Helmwind is a 604e with multiprocessing support, to be fabricated in a new process developed by IBM in Burlington, Vermont. The first ones are expected to be clocked at 200MHz to 250MHz, with 300MHz on the horizon. In the Mac world, Power Computing Corp and Umax Computer Corp are tipped to put it into their high-end systems. A 604e code-named Mach 5 is planned by IBM and Motorola Inc for mid-year, MacWeek hears, but it will still be based on the current architecture, and simply be smaller and use less power – which means it should start out at 300MHz and move beyond 400MHz in 1998. The processor’s Level 2 caches are said to offer better floating-point performance than older versions. Working alone, Motorola is said to have a 300MHz 603e called Golden Eye for launch before mid-year.
