1. Power On Sequence
Sephiroth Kwon
GRMA

2. OUTLINE General Power On Sequence Power On Sequence (P5Q3)
Power On Sequence (M3N78-VM)
No Power Problem Debug Point

3. General Power On Sequence
PSON#
ATX
TOP VIEW
PWRBTN
1/0
PANNEL
+ 5
+ 12
5VSB to 3VSB
Linear Reg.
Cap./
Res.
3VSB 1
+ 5
5VSB
- 5
PWOK
5VSB 1
GND
GND
GND
+ 5
GND
GND
PSON
+ 5
GND
GND
South
Bridge
Super I/O
IT8282
- 12V
+ 3V
+ 3V
+ 3V
PSON Pull low circuit
PSON
PWRBTN

4. General Power On Sequence
+ 12
5VSB
PWOK
GND
+ 5
+ 3V
- 12V
PSON
- 5
CPU SOCKET
(2)
CPURST
(5)
PG1
IDERST
Circuit
IDE SLOT
PWROK
(4)
(3)
PCIRST
PCI SLOT
North Bridge
Further describe, applicability, predigest
Circuit
PSON
South Bridge
(1)
PWRBTN
PANNEL

5. Power On Sequence (P5Q3 Sample)
S_PLTRST
GMCH
H_CPURST#
B_ATX_PWROK
POWER
SUPPLY 10
USER PRESS
CRTL+ATL+DEL
O_PWROK
O_PWROK_NB 7
O_PSON# 6
Super I/O
O_PCIRST#_PCIEX16_12 9
PCI_PCIEX16
O_PCIRST#_PCIEX1_123
O_PCIRST#_SLOT 9
USER PRESS
POWER BTN 3
O_PWRBTNIN#
PCI_PCIEX1
O_RSMRST# 2
S_SLPS3# 5
S_SLPS4# 5
O_PWRBTN 4
O_PWROK 7
O_KB_RST#
PCI SLOT 7
P_VRM_GD
EPU
User press
Rest button
RSTCON#
S_PCIRST# 8
ICH10R
TPM
S_TRCRST# 1
JMB363
User clear
CMOS
VA6308P 8
H_CPUPWRGD
VCORE
S_PLTRST# 8
CPU
LAN

6. Power On Sequence(M3N78-VM)
ATX
Power
SIO
ITE8712F
MCP78
CPU
PCI SLOT 1,2
PCIE X1
VRM
PCIE X16
IDE Port
13. PCI_RST#
13.PCIERST#
11. IDE_RST#
2. PWR_BTN#
13. PCIE_RST#
1.RSMRST#
4.SUSC#
3.SIO_PWRBTN#
4.SUSB#
5. PSON#
6. 12V
6. 5V
6. 3V
11.SIO_RST#
7.PWROK_SB
8. VCORE_EN
9. VCORE_PG
VHT_EN
14. CPU_RST#
12. CPU_PWROK#

7. No Power Problem Debug Point
POWER UP PROBLEM
Check if any burned components or traces
Check no voltages short with GND such as +5, +12 , +5VSB, +3, -12, +3VSB, VCORE 1.5V, 2.5V
Check Battery voltage
Check X’tal KHz
Check 5VSB ,3VSB, PWRBTN#
Check PSON signal & related circuit

8. Thank You!