ASUS TUF X570-PLUS doesn't power on: no VRM_EN signal.

[ShadowAi]

Hello, I have an issue with the motherboard. Specifically, it doesn't power on, more precisely, the POST initialization doesn't occur.

Let me start from the beginning, the motherboard suddenly stopped working one day. There are no beep signals from the speaker, and the debug LEDs are not lighting up. After inspecting it under a microscope and using thermal imaging, I didn't find anything that could be damaged.

After that, I began voltage measurements, in which I noticed the absence of VDDQ, VDDP, VTT, and VPP lines. Later, I checked if there is an EN state on these lines, and there wasn't for VDDQ and VPP.

I tested the motherboard with two different processors. Based on my measurements, I suspected that the NCT6798D-R might be damaged, but even after replacing it, the same problem and results persisted. When I checked with an oscilloscope, there was nothing in the SMB.

Configuration:
01-ASUS TUF GAMING X570-PLUS
02-AMD Athlon 200GE
03-Adata 1x8GB 3000Mhz CL15
04-Gigabyte GeForce GTX 1050 Ti WF OC
05-SilentiumPC L2 Vero 600W

SLP_S3# 3.37V
P_VRM_EN_5 0V
O_RSMRST# 1.827V
P_VCORE_EN_G_1_10 5.2V
PSON# 0.0167V
ATXPGD 3.4V
PWROK 3.5V
3VSBSW# 5.2V
DEEP_S5 0V
RESTCON# 3.37V
5VSB_GATE# 0.0468V
+12_CPU 12.1V
VCORE 0V
VDDSOC 0V
+5V 5.0V
+5VSB_ATX 5.01V
+5VSB 5.0V
VDDQ 0V
VTT_DDR 0V
VDDP 0V
VPP_DDR 0V
+1.8VSB 1.81V
VDDPSB 0.913V
+1.0VSB_PM 1.01V
+1.2V_PM 1.2293V
+5VSB_DUAL 4.6V
+3VSB 3.38V
+3VSB_ATX 3.34V
+1.8V (CPU&SB)1.812V
+1.0V_PM 1.0V
P_VDPP_CON_10 10.6V
P_VTT_DDR_EN_10 3.4V
P_VPP_DDR_EN_10 0.0032V
VPP +5VSB power supply 5.18V
P_VDDQ_VCC_20 5.2V
P_+VDDQ_PG1_10 0.0012V
P_VDDQ_REFOUT_10 0.0065V
O_APU_PWRGD 0.102V
O_KBRST#_R 3.4V
PQ5018:
1 0.755V P_VRM_12V_EN_10
2 0.138V P_+VCORE_EN_5V_10
3 0.2V P_VRM_Q_EN#_10
PQ5019:
1 0.686V P_VRM_5V_EN_10
2 0.0626V P_+VCORE_EN_3V_10
3 0.138V P_+VCORE_EN_5V_10
PQ5020:
1 0.635V P_VRM_3V3_EN_10
2 0V GND
3 0.0625V P_+VCORE_EN_3V_10
PQ5021:
1 0V GND
2 0.189V P_VRM_Q_EN#_10
3 0.0047V P_VRM_EN_5
4 0V GND
5 0.0047V P_1V2_M#
6 0.0020V P_VRM_EN_5
S_RTCCLK voltage jumps from 0.72V to 1.1V on the meter, on the oscilloscope, 32Khz rectangle probably from the chipset clock.
S_CK_33M_LPC is 3.3V but I didn't see 33Mhz.
H_LPC_RST#_R 0.0020V
Link to the boardview of this motherboard + schematics of boards based on the NTC NCT6798D-R and Power Sequence ***************Google drive link removed***************

MOD Edit - Please share schematics and boardviews by posting them in the Bios & Schematics sub forum where others can find and use them

Asus Prime H510M-K Boardview & Repair guide https://www.badcaps.net/forum/troubl...w-repair-guide
Asus ROG Strix X570-I Gaming Schematic https://www.badcaps.net/forum/troubl...ming-schematic
Asus Prime Z390-A Rev1.02 (60MB0YT0-MB0A01) Schematic https://www.badcaps.net/forum/troubl...0a01-schematic
Asus TUF GAMING X570-PLUS (WI-FI) r1.04 Boardview https://www.badcaps.net/forum/troubl...1-04-boardview
Asus STRIX B450-F GAMING r1.0 Schematic https://www.badcaps.net/forum/troubl...r1-0-schematic

[прямо]

Trace where the VRM_EN signal is coming from and what voltage it should be when it's working normally. If there's a component that generates this signal but doesn't work, remove it or disable it, and then inject voltage into VRM_EN to see if the rest of power up sequence will continue and mobo will start.

Sorry I can't look at the boardview and schematic. I'm browsing the forum with my phone.

[taghia]

hi i have the same problem with asus tuf gaming b650m plus no VRM_EN signal and they have the same symptoms with yours no q led no beeps it just power on
the signal for me is form 3 mosfet
if you resolved the problem i hope you post how you did it