HP 650 G2 Troubleshooting Help

[ionut68]

Hi
I'm asking for help with the CIRCUS-6050A2723701-MB-A02 motherboard that I can't turn on.
I have typed into memory all the bios posted on this forum, with all pretty much the same result: Turns on the fingers, POWER, AUDIO on/off, and WRILES LED, and after 10-15 seconds the fan starts up with increasing speed.
All voltage sources are OK except for two that don't draw any voltage:
U66010 and U66310 (SIC631) = 0V I measured with ohmmeter against ground the outputs after coil L66010 and L66310 = 5,311Ohm
I measured the voltages on pins U66010 and U66310:
Voltages with power OFF button
Pin 1=0V
Pin 2=2V
Pin 3=5.2V
Pin 5=4.9V
Pin 7=0V
Pin 8,.....11=19,7V
Pin 16,....23=0V
Pin 29=5,2V

Voltages with power button ON
Pin 1=2,58V
Pin 2=0V
Pin 3=5,2V
Pin 5=4,9V
Pin 7=0V
Pin 8,.....11=19,7V
Pin 16,....23=0V
Pin 29=5,2V


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[ionut68]

Re: HP 650 G2 Troubleshooting Help

Can anyone tell me what the voltage should be on those two sources?
What is the value of the output resistance to ground?

[keczuk]

Re: HP 650 G2 Troubleshooting Help

did u solve this problem ? i have same issue ?

[Sephir0th]

Re: HP 650 G2 Troubleshooting Help

In these cases it is often a communications issue between the VRM Controller and the CPU, which usually means the CPU is bad. Measure Power Inputs, Enables, PGood, VRHOT# and ALERT# to have a basic overview