Hi everyone, over the past few months i have taken a deep dive into motherboard diagnostics and I love the challenge. Currently im trying to learn all about the signals that travel around the motherboard, such as frequencies, enable signals High and Low logic states etc. And i have been learning to read and using the Schematics for this board that i requested here on Badcaps forum, from a few months ago, this is such a great place for these.
I’ve been working on a GA-970A-DS3 (rev. 1.0) that does not post. This motherboard has been my main learning board. I would like share some of my findings to hope that someone can guide me in the right direction as to what the possible reason for this board not having post code could be. As I have 4 other desktop motherboards with the same fault, leading me to believe this problem is common.
I will start by saying that I have flashed and verified both bios chips. Next, the diagnostic card shows no numbers, no post codes, and the RESET LED just flashes over and over. There is alot here so I will break it down and give what seems to be the most interesting findings.
The PS_OUT and SLP_S3 are pulsing (repeating) in time with the RESET LED on the diagnostic card. There is no RSMRST# signal before or after the Power button has been pressed. SLP_S5 is signal LOW. CLKIN on the super IO has No Frequency Expected 48Mhz from Clock IC. CPU_PG on Super IO has No signal
The following is everything i have done/checked far
. Flashed and verified both bios chips
. Checked the Clock IC 48MHz clock output on pin 1 is ok. X1 and X2 both have 14.318MHz
. Checked RTC Crystal, it has 32.768 kHz
. Checked for shorts on North Bridge, no shorts.
. Tested all fuses, all are ok
. Check main power rails for shorts, including 12V CPU input, all ok
. Checked all Inductors for shorts, no shorts
. Checked the PCI socket on pin 16, PCICLK 1 for shorts to the Northbridge, no shorts
. Checked the PCI-e socket on some pins going to the Northbridge, no shorts
. Check the motherboard using a thermal camera, and i do not see any concerning temperatures
The Following Signals were Observed using Oscilloscope, or logic probe
. Tested 3VSB going to the Super IO, it is present
. Checked for PS_OUT signal on Super IO pin 72, it is pulsing
. Checked RSMRST# signal, there is nothing, no signal
. Checked SLP_S3 going to KBC from South Bridge, on pin 71. It is also pulsing like PS_OUT
. Checked SLP_S5 it is signal LOW
. Checked PWROK on VRM Controller IC, is it 3.3V
. Checked EN on VRM Controller IC, is it 5V, and CPU does get warm.
. Checked PGOOD on VRM IC 1.5V im not sure if this is HIGH or LOW Signal maybe an intermediate state.
. Checked VCORE_PWOK it is LOW
. Checked CLKIN on the super IO has No Frequency. Expecting 48Mhz from Clock IC
. Checked CPU_PG on Super IO No signal
Thanks for taking the time to read.
I’ve been working on a GA-970A-DS3 (rev. 1.0) that does not post. This motherboard has been my main learning board. I would like share some of my findings to hope that someone can guide me in the right direction as to what the possible reason for this board not having post code could be. As I have 4 other desktop motherboards with the same fault, leading me to believe this problem is common.
I will start by saying that I have flashed and verified both bios chips. Next, the diagnostic card shows no numbers, no post codes, and the RESET LED just flashes over and over. There is alot here so I will break it down and give what seems to be the most interesting findings.
The PS_OUT and SLP_S3 are pulsing (repeating) in time with the RESET LED on the diagnostic card. There is no RSMRST# signal before or after the Power button has been pressed. SLP_S5 is signal LOW. CLKIN on the super IO has No Frequency Expected 48Mhz from Clock IC. CPU_PG on Super IO has No signal
The following is everything i have done/checked far
. Flashed and verified both bios chips
. Checked the Clock IC 48MHz clock output on pin 1 is ok. X1 and X2 both have 14.318MHz
. Checked RTC Crystal, it has 32.768 kHz
. Checked for shorts on North Bridge, no shorts.
. Tested all fuses, all are ok
. Check main power rails for shorts, including 12V CPU input, all ok
. Checked all Inductors for shorts, no shorts
. Checked the PCI socket on pin 16, PCICLK 1 for shorts to the Northbridge, no shorts
. Checked the PCI-e socket on some pins going to the Northbridge, no shorts
. Check the motherboard using a thermal camera, and i do not see any concerning temperatures
The Following Signals were Observed using Oscilloscope, or logic probe
. Tested 3VSB going to the Super IO, it is present
. Checked for PS_OUT signal on Super IO pin 72, it is pulsing
. Checked RSMRST# signal, there is nothing, no signal
. Checked SLP_S3 going to KBC from South Bridge, on pin 71. It is also pulsing like PS_OUT
. Checked SLP_S5 it is signal LOW
. Checked PWROK on VRM Controller IC, is it 3.3V
. Checked EN on VRM Controller IC, is it 5V, and CPU does get warm.
. Checked PGOOD on VRM IC 1.5V im not sure if this is HIGH or LOW Signal maybe an intermediate state.
. Checked VCORE_PWOK it is LOW
. Checked CLKIN on the super IO has No Frequency. Expecting 48Mhz from Clock IC
. Checked CPU_PG on Super IO No signal
Thanks for taking the time to read.
