Phipli
Well-known member
Try a different RAM SIMM and clean the CPU pins again. After that, I'm sorry to say that the next thing to try is a replacement processor.
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Power Mac 7500
- Thread starter ExplorerZ
- Start date
macuserman
Well-known member
Where are you located? I can probably help out with a couple known good components to test.
ExplorerZ
Well-known member
The CPU gets incredibly hot to the touch after a minute.
ExplorerZ
Well-known member
Acworth, Georgia
ExplorerZ
Well-known member
What should the voltage be? And how do I check it,
ExplorerZ
Well-known member
Cut that. After checking again after changing the switches up like you said earlier, it gets just a little warm after a minute
macuserman
Well-known member
I’m in Woodstock so I might be able to help you out.
Phipli
Well-known member
Yeah, I halved the clock speed. Sounds like the processor is trying to run.
ExplorerZ
Well-known member
Tried looking up YouTube videos but none of them were about vintage computers. I also don’t know how much it should be outputting.
Phipli
Well-known member
Youtube is a weird place to look for a picture
Not verified. Take care, do not short it. Best to only have one probe on the power connector, pick up ground from somewhere else.
Best way might be to clip the negative probe to something that is grounded, (make sure it does not slip), then poke the positive probe in the back of the connector.
Make sure your probes are in the correct sockets on the multimeter for measuring Voltage, if you plug them in wrong, you are likely to kill the PSU.
If you haven't done this before, it might be worth asking a friend with practice doing this to show you how to do it?
ExplorerZ
Well-known member
Will this multimeter work?Youtube is a weird place to look for a picture
Not verified. Take care, do not short it. Best to only have one probe on the power connector, pick up ground from somewhere else.
Best way might be to clip the negative probe to something that is grounded, (make sure it does not slip), then poke the positive probe in the back of the connector.
Make sure your probes are in the correct sockets on the multimeter for measuring Voltage, if you plug them in wrong, you are likely to kill the PSU.
If you haven't done this before, it might be worth asking a friend with practice doing this to show you how to do it?
ExplorerZ
Well-known member
10 pin molex connector,Youtube is a weird place to look for a picture
Not verified. Take care, do not short it. Best to only have one probe on the power connector, pick up ground from somewhere else.
Best way might be to clip the negative probe to something that is grounded, (make sure it does not slip), then poke the positive probe in the back of the connector.
Make sure your probes are in the correct sockets on the multimeter for measuring Voltage, if you plug them in wrong, you are likely to kill the PSU.
If you haven't done this before, it might be worth asking a friend with practice doing this to show you how to do it?
1&6 are 3.7v
2&7 are 3.7v
8&3 are 3.7v
9&4 are 3.7v
10&5 are 3.3v
22 pin molex connector,
1&12 are 4.9v
Everything else is 0v, probably messed something up
Phipli
Well-known member
No 12v, -12v -5v?
ExplorerZ
Well-known member
I’m having trouble turning on the power supply to test the 22 pin.
ExplorerZ
Well-known member
Ok, I’m getting 5v from black on 11 and red on 22. Pretty sure that’s supposed to be 12v. May just be because it’s not turned on
ExplorerZ
Well-known member
As long as this paperclip is in there, it’s on
ExplorerZ
Well-known member
Still having trouble getting readings though
Phipli
Well-known member
Erm, no. Measure from the /back/ of the connector with it plugged into the board and it powered on.
ExplorerZ
Well-known member
Oh... That makes more sense.
