Have a 3332 that gives a green light, then switches over to a faint orange light. No fan. PPBUS_G3H is reading at .7v at multiple points on the board. U7000 is new, all components around it check out fine. 20.25v off the io board. no blown fuses (of course). chrgr_dcin at u7000 is 20.25 pin 3 of u7000 is reading somewhere around 4.5v. Then suddenly, the charger only goes green, and shorts out and shuts off (to where I have to unplug it to reset it.)... any thoughts?
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3332 ppbus_g3h .7v
- Thread starter Rford
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larossmann C7620 was shorted. Restored PPBUS_G3H Now quarter fan spin. No vcore. Checked around on vcore found bad R1360, switched it out for a good one. Same. Ideas? Vcore has a ton of componentry. In diode mode, vcore is 0.000 (shorted)
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vcore is not shorted, tell me why.
It's not a short.
These aren't exact numbers, just guessing, but let's say a CPU uses 45w of power.
Let's say a CPU runs on 1v of vcore.
What resistance to ground do you need in the ohm's law calculator to get 45w out of 1v? http://www.ohmslawcalculator.com/ohms-law-calculator Try it out.
Chips that use LOTS of wattage at low voltage will have a low resistance to ground, it is just natural. Same thing with a speaker. If you look at receivers where it says 100w into 8 ohm load, 175w into 4 ohm load. It is able to deliver more power/current at the same voltage if the resistance is lower. A 3 ohm speaker is essentially a 3 ohm "short" but that does not mean it is "broken."
These aren't exact numbers, just guessing, but let's say a CPU uses 45w of power.
Let's say a CPU runs on 1v of vcore.
What resistance to ground do you need in the ohm's law calculator to get 45w out of 1v? http://www.ohmslawcalculator.com/ohms-law-calculator Try it out.
Chips that use LOTS of wattage at low voltage will have a low resistance to ground, it is just natural. Same thing with a speaker. If you look at receivers where it says 100w into 8 ohm load, 175w into 4 ohm load. It is able to deliver more power/current at the same voltage if the resistance is lower. A 3 ohm speaker is essentially a 3 ohm "short" but that does not mean it is "broken."
You can also measure the ohm value you get when you short your multimeter leads: this is your dead short ohm value reference.
Now check resistance to ground on vcore and compare with your dead short reference.
You can also inject 0,5v on vcore, and see if you measure 0,5v with multimeter.
Now check resistance to ground on vcore and compare with your dead short reference.
You can also inject 0,5v on vcore, and see if you measure 0,5v with multimeter.