• Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU

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#1 Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU


by Logic 26 February 2025, 15:17
Cześć,
Jak w tytule posiadam laptopa Aspire VN7-791G-77R4 z płytą główną Poseidon 840M 14204-1M (Obsada i7 4gen, nvidia 850M).
Problem w laptopie jest tego typu, że wszystkie napięcia pojawiają się poza CPU_VCORE.
Laptop włącza się, podświetlenie klawiatury świeci, wentylatory kręcą się.
Zaprogramowałem BIOS sprawdzonym wsadem ale wciąż to samo.
Myśląc, że uszkodzona jest przetwornica wymieniłem ją ale problem dalej występuje.
Układ to TPS51631.
Podaję pomiary wykonane na układzie:

1 H_CPU_SVIDDAT - 0V
2 PWR_VCC_VDD - 3,37V
3 IMVP_PWRGD - 0V
4 PWR_VCC_PWM3 - 1,68V
5 PWR_VCC_PWM2 - 1,68V
6 PWR_VCC_PWM1 - 1,68V
7 PWR_VCC_SKIP_ - 5V
8 ALL_SYS_PWRGD_R - 2,91V
9 PWR_VCC_O-USR - 0,6V
10 PWR_VCC_F-IMAX - 0,6V
11 PWR_VCC_B-RAMP - 0.20V
12 PWR_VCC_OCP-1 - 0V
13 PWR_VCC_IMON - 0V
14 PWR_VCC_THERM - 0,12V
15 PWR_VCC_SLEWA - 0,08V
16 PWR_VCC_VBAT - 18,28V
17 PWR_VCC_CSP1 - 0V
18 PWR_VCC_CSN1 - 0V
19 PWR_VCC_CSN2 - 0V
20 PWR_VCC_CSP2 - 0V
21 PWR_VCC_CSP3 - 0V
22 PWR_VCC_CSN3 - 0V
23 PWR_VCC_GFB - 0V
24 PWR_VCC_VFB - 0V
25 PWR_VCC_DROOP - 3,56V
26 PWR_VCC_COMP - 2,11V
27 PWR_VCC_VREF - 1,69V
28 5V_PWR_VCC_V5A - 5,06V
29 GND - 0V
30 POWER_PROCHOT__CPU - 0V
31 H_CPU_SVIDCLK - 0V
32 VR_SVID_ALERT_ - 0V
33 GND - 0V

KBC:
4 3D3V_S0 - 3,3V
84 S0_PWR_GOOD - 3,3V
91 DGPU_PWROK - 3,3V
120 ALL_SYS_PWRGD_C - 2,94V - Tutaj chyba powinno być 3,3V. Coś zaniża napięcie?

Sygnał 1D05V_S0_PWRGD - 3V

Korzystam z wersji boardview do płyty 860M, gdzie również była wykorzystana przetwornica TPS51631, natomiast nie jestem pewien co do pinout'u KBC.
W sekwencji zaraz przed pojawieniem się +VCC_Core jest sygnał DDR_VREF_PWR, gdzie pojawia się 0,68V

Re: Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU


by Google Adsense [BOT] 26 February 2025, 15:17

#2 Re: Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU


by matic 27 February 2025, 09:12
Logic wrote:120 ALL_SYS_PWRGD_C - 2,94V - Tutaj chyba powinno być 3,3V. Coś zaniża napięcie?
Hello!
- Check the resistor R3708 (10kΩ)
- If the resistor is fine, open (cut) the jumper R3611 and remeasure the voltage to ground on the signal line "ALL_SYS_PWRGD_C".

Measure the following voltages to ground:
- On pins 8, 14 of chip U8301.
- On pin 1 of chip U8304.
- On pin 5 of chip PU5103.

#3 Re: Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU


by Logic 27 February 2025, 12:43
matic wrote:Check the resistor R3708 (10kΩ)

Cześć,
Rezystor R3708 10kΩ wlutowany ma 8,8kΩ. Po jego wylutowaniu i sprawdzeniu poza płytą jest sprawny - ma 10kΩ.
Oporności na pinach, gdy rezystor jest wylutowany:
1 3D3V_S0 - 8,2k ohm
2 PCH_PWROK_R - 70k ohm

matic wrote:(cut) the jumper R3611 and remeasure the voltage to ground on the signal line "ALL_SYS_PWRGD_C".

Po przecięciu jumpera R3611 sytuacja bez zmian - wciąż jest 2,94V na linii sygnałowej ALL_SYS_PWRGD_C.

matic wrote:pins 8, 14 of chip U8301

U8301
8 3D3V_VGA_OUT1 - 3,37V
14 1D05V_VGA_OUT2 - 1,07V

matic wrote:1 of chip U8304

1 3D3V_VGA_S0 - 3,37V

matic wrote:pin 5 of chip PU5103

PU5103

Z przeciętym jumperem R3611
5 1D5V_PWR - 0,72V
1 3D3V_PVDD_PWR_1D5V - 3,37V
3 PWR_1D5V_S0_EN - 0,80V

Z polutowanym jumperem R3611
5 1D5V_PWR - 1,49V
1 3D3V_PVDD_PWR_1D5V - 3,37V
3 PWR_1D5V_S0_EN - 2,96V

#4 Re: Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU


by Logic 28 February 2025, 15:50
up

#5 Re: Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU


by matic 7 March 2025, 16:11
Close the jumper R3611 and open (cut) the jumper R3613. Then remeasure the voltage to ground on pin 2 of resistor R3708.

Re: Aspire VN7-791G-77R4 MB: Poseidon 840M 14204-1M - Brak zasilania CPU


by Google Adsense [BOT] 7 March 2025, 16:11

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