Hi to all,
the owner of this machine gave it to me after having opened it to take off the dust from the inside, telling me that after that it didn't start anymore.
I found that one of the DrMOS (AOZ5016QI) on the CPUCORE was shorted between VIN and VSWH, and that one of the two n-mos connected to the power jack was shorted aswell.
I unsoldered the two shorted components and verified that there were no other short circuits, then decided to power the mainboard, firstly with the lab power supply, then with its original HP 200w charger, but the behaviour is the same, the board starts and stops 3 times in a 3 seconds cycle, then startsup again and the capslock makes this pattern:
3 long blinks, 5 long blinks, 3 quick blinks, 5 long blinks, 3 quick blinks , then shuts down itself.
If I try to start it up again, the capslock pattern repeats always in the same way.
I measure all main voltages on the board, and I have :
0.80 CPU CORE (but the value is fixed, i don't see oscillations of the voltage, as if when the CPU was going through differente power states)
1.76 (maybe) VCCSA od PCH
0.00 No voltage on what it seems the VGFX rail (graphic rail for the Intel GPU)
1.19 RAM
0.74 VGA core
1.21 Video RAM
3.25 +3V
4.98 +5V
Seeing how the DrMOS is shorted, it's very likely that the CPU took a strike from +19v directly into its core, but searching on the HP website, the capslock pattern points to the error "This condition indicates that the embedded controller cannot reach the BIOS within the established time limit.", that isn't so relevant to the CPU feeding circuit or input n-mos (neither the IT5570E-256 nor the bios IC are shorted and are very well connected to each other).
I'd like to ask a help from some colleague, since I can't find schematics or boardview of this board (I didn't even identify the CPU power controller made by Alpha Omega, marked as BL211), maybe some have had already experiences with similar boards or CPUs.
Some of you knows if the absence of one of the 4 DrMOS in the CPU feeding circuitry makes impossible for the CPU to start?
Searching into the datasheet of these DrMOS I've seen that they have only the PWM and FCCM pins connected to their controller IC (and phase-side to sense the output voltage), no PGOOD or other outputs, so maybe the board could work even if it has less phases...
I could buy them but they cost around 15€ each so I'd like to think twice before paying for something that I can only use here by now...
Any help would be appreciated
the owner of this machine gave it to me after having opened it to take off the dust from the inside, telling me that after that it didn't start anymore.
I found that one of the DrMOS (AOZ5016QI) on the CPUCORE was shorted between VIN and VSWH, and that one of the two n-mos connected to the power jack was shorted aswell.
I unsoldered the two shorted components and verified that there were no other short circuits, then decided to power the mainboard, firstly with the lab power supply, then with its original HP 200w charger, but the behaviour is the same, the board starts and stops 3 times in a 3 seconds cycle, then startsup again and the capslock makes this pattern:
3 long blinks, 5 long blinks, 3 quick blinks, 5 long blinks, 3 quick blinks , then shuts down itself.
If I try to start it up again, the capslock pattern repeats always in the same way.
I measure all main voltages on the board, and I have :
0.80 CPU CORE (but the value is fixed, i don't see oscillations of the voltage, as if when the CPU was going through differente power states)
1.76 (maybe) VCCSA od PCH
0.00 No voltage on what it seems the VGFX rail (graphic rail for the Intel GPU)
1.19 RAM
0.74 VGA core
1.21 Video RAM
3.25 +3V
4.98 +5V
Seeing how the DrMOS is shorted, it's very likely that the CPU took a strike from +19v directly into its core, but searching on the HP website, the capslock pattern points to the error "This condition indicates that the embedded controller cannot reach the BIOS within the established time limit.", that isn't so relevant to the CPU feeding circuit or input n-mos (neither the IT5570E-256 nor the bios IC are shorted and are very well connected to each other).
I'd like to ask a help from some colleague, since I can't find schematics or boardview of this board (I didn't even identify the CPU power controller made by Alpha Omega, marked as BL211), maybe some have had already experiences with similar boards or CPUs.
Some of you knows if the absence of one of the 4 DrMOS in the CPU feeding circuitry makes impossible for the CPU to start?
Searching into the datasheet of these DrMOS I've seen that they have only the PWM and FCCM pins connected to their controller IC (and phase-side to sense the output voltage), no PGOOD or other outputs, so maybe the board could work even if it has less phases...
I could buy them but they cost around 15€ each so I'd like to think twice before paying for something that I can only use here by now...
Any help would be appreciated
Comment