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I replaced my Power Mac G4 CPU with dual 1.33GHz, but the clock is showing as 1.0GHz.
Posted by: mcmcjohn on 2025-09-22 02:31:43 Hello. The model I have is the Power Mac G4 Gigabit Ethernet. Originally, it had a single-core 1.33GHz CPU, but I wanted to upgrade to a dual CPU. So, I bought a DP 1.0GHz module from a Quicksilver, and I heard that by changing the resistor values, it could be overclocked to 1.2GHz or 1.33GHz. I moved the resistors accordingly to make it 1.33GHz. I also completed the additional 12V power supply modification. However, after booting, both Mac OS 9 and Mac OS X still recognize it as 1.0GHz. Since this model only has a 100MHz bus, is it normal that changing the resistor like this doesn’t make it show up as 1.33GHz?
Posted by: herd on 2025-09-22 07:41:06 Nice work getting that CPU installed in a Gigabit! What did you do for a heatsink?
Posted by: mcmcjohn on 2025-09-23 06:41:32 Nice work getting that CPU installed in a Gigabit! What did you do for a heatsink? I successfully transplanted the single-core 1.33GHz CPU into another Power Mac G4! It’s an excellent processor. In fact, I had already swapped in a Gigabit logic board beforehand just for this CPU upgrade, which is probably why the dual-processor works so well. As for the heatsink, it’s actually a Gigabit dual-processor heatsink (not a Quicksilver one), and I trimmed the left side a bit with a cutter. It turned out to fit perfectly with the Quicksilver dual 1GHz. Then I attached two small fans on the sides for cooling, and now it runs beautifully!
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