Voltage Regulator right but CPU not getting voltage

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thesuperdanb
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Voltage Regulator right but CPU not getting voltage

Post by thesuperdanb »

So decided to take a crack at assembling a ms2 v3. Following the directions I assembled the power supply and when i went to test the cpu socket voltages there was no power except like -0.01 between 19 and 20. The voltage regulator is showing 12 volts closest to db9 then the ground has less then 1 ohm and the farther has v5. Anyone have any ideas thanks in advance. I also looked it over like 20 times for solder bridges and could not find any.
prof315
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Re: Voltage Regulator right but CPU not getting voltage

Post by prof315 »

Probably a backwards diode
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elaw
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Re: Voltage Regulator right but CPU not getting voltage

Post by elaw »

Check voltage on both sides of F1. If you've got 5V (or close to it) on one side and close to 0 on the other, you've got a short somewhere or a component installed backwards - D19 is one possibility but there are others.

If you have 5V on both sides of F1, check both sides of L1 and L2. If you get 0V on one side of either, that part could be bad or have a bad solder joint.
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