Readers have been outspoken about my assertion that Apple will go with Pentium 4 in Intel-based Macs. I stand corrected: Intel is sweeping NetBurst from its roadmap in favor of Pentium III-derived designs. But with the Mac, it comes down to what Mac users want and expect. Hyper Threading makes little difference on benchmarks, but it makes a considerable difference in user experience. The smooth, flowing UI that Readers have been outspoken about my assertion that Apple will go with Pentium 4 in Intel-based Macs. I stand corrected: Intel is sweeping NetBurst from its roadmap in favor of Pentium III-derived designs. But with the Mac, it comes down to what Mac users want and expect. Hyper Threading makes little difference on benchmarks, but it makes a considerable difference in user experience. The smooth, flowing UI that is the Mac’s trademark–interaction with the user is a Mac client’s top priority unless load demands otherwise–isn’t workable on any Pentium M/Centrino notebook I’ve got. It is quite workable on the Hyper Threaded, single-core Pentium 4 desktop in my lab. On a dual-processor, dual-core, non Hyper Threaded workstation I have here, the user feel is still choppy under load.This isn’t news to Intel. In a session I attended at this year’s Intel Developer Conference, a senior Intel engineer put it plainly: When you’re hand-optimizing for multiple threads, code to prefer Hyper Threading first, then dual core, then SMP. The distance between cores makes a big difference. HT is the only x86 technology Intel’s got that shares a single cache.Remember Steve Jobs’ demo at the Power Mac G5 launch? The 3 GHz dual Xeon box eventually filled up its caches and cleared the bus to catch up to Power Mac G5’s rendering speed. But I would have cheered for the G5 if it had rendered 25% slower. The G5 started and finished rendering at its top speed. Xeon’s dut….dut…dut..dut.dut.dutdutdut had “not suited to this task” written all over it. I don’t even want to think about Steve’s demo of eight (more? I can’t recall) mixed stereo audio tracks playing in real-time while the dual Xeon box choked and sputtered. I do digital media work on a Power Mac G5. I really am concerned about what would happen to my productivity in and rapport with Apple’s Pro Tools if they were running on Pentium D or its progeny. If the drive isn’t silky smooth, the what-if compositing and effects that are my working style will suffer.I’d use Pro Tools on a single-processor Power Mac with confidence. I run Final Cut Express on my 1.5 GHz PowerBook. But Centrino? Pentium D? I’ll work hard to open my mind to the idea. A Pentium 4 EE with HT on a 1 GHz bus seems nowhere near as wide a leap from G5. An Opteron or Athlon FX is no leap at all.As for what Mom and Pop let little Skyler use to surf in his jammies before bed, that isn’t remotely on my radar. The power utilization characteristics of the 80486 are very appealing and the compute capabilities are overkill for AOL. Apple’s consumer market will be overjoyed with Pentium M. ——– Technology Industry