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aalberto
Nov 29, 2006, 11:22 AM
Hi. I have changed out the power supply on my PowerMac G4 to a 430w model (converted a PC power supply to work on Mac). I have made sure that the wiring matches exactly the original power supply, except for the 28w line, which I was told to connect any 5v line to it. Long story short, everything works just as before. I have then purchased an ATI Radeon 9800 video card. Popped it in my computer and connected it to this same power supply but the video card does not work. The guy I bought it from (on Ebay) said there might be a problem with my power supply. Checked the leads and the red line outputs 5v and the yellow one 12v.
Does the Mac-compatible power supply units put out a different voltage than a PC one? Again, all of the other components on my computer work except the video card. Does the video card itself expect a certain voltage before it is activated?
Specifications of my computer: PowerMac G4 AGP Graphics, 1.6Ghz CPU (upgraded PowerLogix CPU), 1Gb Ram, 80Gb HD, DVD-RW, MacOS X 10.4.8