I just saw this on MacBidouille, complete with "About This Mac", Powerlogix CPU Director and Carbon Fractal Demo screenshots. http://www.macbidouille.com/niouzcontenu.php?date=2003-06-05#5719 For the French impaired , here's the translation: "We're currently testing the Giga Designs 1.4 GHz [G4] upgrade card. As expected, this card is overclockable. It's been behaving quite well at 1.5 GHz for several hours now. It wouldn't take much to get it to run at 1.6 GHz. The machine boots, runs benchmarks, but is unstable. Tweaking the core voltage doesn't help. Upgrading the heatsink/fan would probably be necessary. Meanwhile, it's the first time I see a Carbon Fractal Demo result above 6000 on a single-processor machine!! The best is yet to come: This is the first single-processor upgrade card to wake from deep sleep on my G4! Lionel" This makes for a very interesting upgrade for people with a modeling/audio/Photoshop workstation, as dual-processor doesn't make a big difference in real-world speed, in these cases. Especially when you take upgrade card price into consideration. Rendering is another story. Another thing of interest, is that judging from their screenshots, they were trying it on an old PowerMac G4 with the 100MHz bus. The more recent 133 MHz bus machines should make this upgrade a fair bit zippier, since the processor won't be so starved for data. The thing that I find very educational about this though, is the 6 Gflop benchmark result. According to Motorola's literature, a 1.6 GHz G4 should get a much higher score. This just underlines how badly the slow FSB cripples the processor. The 1.8 GHz PPC 970 is rated at 14.4 Gflops. But with it's 450 Mhz (900 Mhz effective) bus, I'm sure the final product will actually deliver close to this performance.