.G3
- The Next Generation is here |
Fall 1997 Measuring CPUs by comparing the megahertz is like thinking your VW running at 3000 RPM is better than a Ferrari running at 2800 RPM. The whole concept of megahertz is irrelevant unless you factor in all the other aspects of CPU card design. First of all, CPU performance is almost trivial unless it's considered in light of the work you actually perform on your machine. Conclusion: Don't get hung up on performance. If you don't need it, don't buy it. A Ferrari makes a nice, albeit expensive, set of wheels, but a rotten taxi in Manhattan. Even if you can afford it. The AIM alliance (Apple, IBM, and Motorola) introduced the original 601 in Apple computers a computer lifetime ago, in March of 1994. The 601 with all its variations belonged to the first generation of Power PC chips. CPU performance ran from a measly 50MHz to the then-blistering 120MHz in the last of the line. The 601 CPU packed as many as 3-million transistors into a die made with .6 micron technology which meant the CPU was both big and produced a lot of heat. But that's only in comparison to the second and third generation AIM CPUs. Then, as now, the Intel CPUs are so large and produce so much heat that they make great hot dog grills. The first generation of Power PCs chips measured a little over an inch-and-a-quarter in size and generated about 20 watts of heat for the fastest CPUs. With the second generation of Power PC CPUs, introduced in Apple computers during May of 1995, die size dropped to a quarter of the size of the 601 and while speed soared, the heat generated by a 604e 200MHz was slightly less than that of a 120MHz 604. The second generation line included the 603, the 603ev, 604 and 604e, a 604er used in the forthcoming 9600/300 and 350MHz and even a 620 server CPU. The later variations packed as many as 8-million transistors into a three-quarter-inch-square chip. Meanwhile at Intel, the weenies roasted. With this second generation of processors, the AIM alliance began to take advantage of speed-enhancing features available all along. The 604e came out of the chute with L1 cache increased to double that of the 604 and that's where the 604e gets most of its speed boost, about 30% over that of a 604. Many users bandy the term cache around without completely understanding it. Cache is nothing but high speed memory. L1 cache generally refers to on-the-processor cache, very fast and very expensive. L2 cache generally means off-the-processor cache. With the G3 or third generation of Power PC processors, the L2 cache and its use becomes ultra important. In the first and second generation of PCI Macs with removable CPUs; the 7500 through the 9600, L2 cache came in the nature of cache way out on the motherboard (dumb). The signal-to-noise ratio was so weak that all cache had to be ultra-high specification to work at all, and L2 cache, installed either as a DIMM or, in the case of the 9500/9600; soldered, cost a bomb because so much of it had to be rejected by the manufacturer. L2 cache can take three forms, (1) motherboard, or cache totally removed from the CPU daughtercards. It's inefficient and performance is limited to constraints based on the computer bus speed. Cache performance is bus speed limited. (2) In-line cache. This cache lives on the daughtercards, which is good. But it's still limited by bus speed. With UMAX and the new Apple In-line cache in the upcoming 8600 and 9600, some multiple of bus speed provides the limiting factor. Rumors suggest Apple will run the In-line cache at a 100MHz speed on a 50MHz bus. And (3) Backside L2 cache, which is soldered on the daughtercard and runs on its own extra-fast bus, (not the system bus used by regular L2 cache or In-line) and is the fastest, most efficient and stable form of cache. The CPU is, and always will be, the fastest part of a computer. When the CPU has to wait four or five cycles to let cache catch up with it to provide the necessary data or program instructions, you lose potential performance. NewerTECH's G3 series of CPUs get their go-power from two primary ingredients. The speed of the CPU chip and use of Backside cache. The Power PC 750 is the chip name. It's third generation (G3) and had a code name (Arthur) mostly meaningless and soon-to-be-forgotten. It's a 750 chip. 750 is just a number like a 601 or 604. The MAXpowr G3 250 /125 has 512Kb of Backside cache running at 125Mhz. It's very important to understand that the Backside cache bus is independent of the system bus and is a function of the CPU speed (unlike the slower Inline cache). But what about the system bus speed which is what everyone has been thinking is so darned important? If the Backside cache speed is not linked to the system bus the way the Inline cache is, what about system bus speed? Turns out it's pretty meaningless. Newer's tests showed almost no variations in total performance between bus speeds as low as 30MHz to as fast as 60MHz. Or in other words, forget system bus speed, it means little in terms of performance enhancement. Newer has opted for a slower, but far more stable, system bus speed with the MAXpowr G3 line. Think about cache bus speed when you need to compare performance. Backside cache will always outperform Inline cache. And Inline cache will always outperform standard off-the-daughtercard cache. The G3 has a so-far hidden and unrealized benefit. When it gets bored, you can put it to sleep. And having the ability to put a CPU into a sleep mode means you can use the chip in a Powerbook upgrade. The G3 is small, fast, produces little heat and uses a tiny amount of power. It's a natural for Powerbooks and while no one has come up with G3 upgrades for notebooks yet, you can bet your sweet bippy the design-types are trying to figure out how. If you can plug one of these little beauties into a 9500 or 7500, you could probably figure out how to plug one into a Powerbook 540. And have a CPU upgrade with both blistering performance and low cost. The more of them you produce, the lower the price drops. Newer Technology has added a new concept to the upgrade path provided by Apple, Power Computing and UMAX. For the first time in history, upgrades make economic sense. Fall 1997 Home.................[ top ]...............CPU upgrades 283 |