Chip level repairing Classroom Notes
The motherboard is the main board in the system, and it is having “malty layer printed circuit board” and it is Manufacturer with Epoxy Material.Motherboard of 3 types
- Server Motherboard
- Desktop Motherboard
- Laptop motherboard
- In the desktop motherboard, (or) laptop motherboard, minimum, and maximum the only one processor. We are inserting, and this processor frequency is maximum 3.6 GHz in this motherboard maximum RAM capacity is 8GB supporting.
- In the motherboard server minimum one processor (and) maximum 64 and above processors we can insert, and this processor frequency is minimum 3.GHz and in this motherboard supporting RAM 512GB and above also.
The desktop motherboard again classified into four types
- Pentium 1
- Pentium 2
- Pentium 3
- Pentium 4
Pentium – III
810, 810E, 815, 820
Pentium – IV
845, 865, 915, 945, 965, DG31, DG33, DG41, DG45
P-III Mother board’s Identification
- It is having AT power supply>> 6+6=12 pins connector & It is having ATX SMPS 20 pin
- It has ISA slot >>it is black color>>having 8-bits and 16 bits
- It has PCI slot>>it is WHITE color>>having 82 bits
- It has IDE1, IDE2>>40 pins connector
- It has floppy disk drive >>34 pins connector
- It has DIMM RAM slot >>it has 168 DIMM package connector
- Processor supports 450Mhz to 1.3Ghz
- Ram support 64MB to 256Mb
- It is having AGP slot >> it is in brown color>>having 64 bits
It has AMR slot >> it is brown color>> having 64 bits
- It has slot processor and socket processor
Slot no.1 – 242 pin
Slot no.2 – 330 pin
Socket no – 370
P-IV Mother board’s Identification
- It has PCI slot >>it is WHITE color >>having 32 bit or yellow
- It is having IDE1,IDE2>> 40 pins connector
- It has floppy disk drive>>34 pins connector
- It has DIMM RAM slot >> it is having 168 pins DIMM package
- It is having ATX, power supply>> 20 or 24 or 28 pins connector
- Processor supports 1.5 GHZ to onwards
- RAM support 128 MB to 4 GB
- It has AGP slot>> it is brown color>> having 64 bits
- It has CNR slot>> it is brown color >>64 bits
- It has ATX SMPS 20 pin (or) 24 pin (or) 28 pin connector.
- It has SATA port seven pin connectors.
- It is having AGP slot, (or) EPCI slot, PCI slot, and CNR slot.
- It supports RAM maximum 8GB.
- It has the socket Processor
Socket No- 423
Socket No- 478
Socket No- 775
Socket No- 462
Socket No- AM 2+
Socket No- 939
Socket No- 752
PCI: – Peripheral connector interface.
It is 32-bit slot 33MHz Frequency No. of Pins 120 this is also called as universal slot be cows of any card we are inserting in this Slot (VGA Card, LAN Card, SOUND Card, TV Tuner, Modem Card, etc…).
Pin- Express (or) Extended peripheral connector interface.
It is the 64-bit slot 66MHz Frequency No. pins is 184 In this slot we are inserting the EPCI Graphic card this slot speed is 16x.
AGP: – the Accelerated Graphic Port.
It is the 64-bit slot 66MHz frequency No. pins is 124 In the slot we are inserting the AGP Graphic card this slot speed is 8x maximum.
AMR: – Audio modem raiser.
It is the 32-bit slot 33MHz frequency No. pins is 46 In the slot we are inserting the 32-bit modem card.
CNR: – Communication network raiser.
It is the 64-bit slot 66MHz Frequency No. pins 60. In the slot, we are inserting the 64-bit modem card.
It is the small BGA (Ball Grid Array) It is fairest to the processor It will control the signal of USB signal Audio signal PCI slot signal and Input-output signal except display signal this is also called as IOCH “input-output controller hub.”
It is the big BGA (Ball grid array) It is nearest to the processor, and it will control the signal of the display signal and processor signal and a RAM signal. The north bridge is also called as MCH “memory control hub.”
MANU FETCHER CAMPINESS OR SOUTHBRIDGE AND NORTHBRIDGE
SMD IC: – Surface mountain drives integrated cruet
The SMD IC Dun by 3. Functions
- Power management function
- Generating the osculating (or) clock signal
- Error employ a tire
MANU FETCHER CAMPINESS ARE SMD IC
- SUPER IO
RISC: – Red used instruction set control
CISC: – Complex instruction set to control
CRISC: – Complex red used instruction set control
RISC PROCESSER:- Single take;
Ex :- 1+1+1+1= 4
Ex:- (1+1) (2+1) (3+1) =4
RISC Processer and CISC Processer used Desktop and Laptop.
MANU FETCHER CAMPINESS ARE MICRO PROCESSORES
NATIONAL SEMY CONDECTOR
P-I, P-II, P-III, P-III Celeron, P-IV, P-IV Celeron, Cetrino
CISC Processers (Desktop and Laptop)
Dual core, Dore2 Dual, Core i3, Core i5, Core i7
Based on the Physical Stretcher Micro Processer or 2types
- Slot Processer
- Socket Processer
PINS – 121+121=242
In that socket, Processor also 2 types
- Pin Processer
- Pinless Processer (or) Dot Processer
PGA – Pin grid array
LGA – Line grid array
BIOS:- Basic Input Output system
Requirement of BIOS
- Identification of components whatever the devices the motherboard
- Booting purpose
- Security purpose
Based on the physical structure BIOS is 3 types
- Horizontal BIOS (or) Flat BIOS – of pins
- Square BIOS – 32 pins
- 8pin BIOS – 8 pins
Manufacturer companies (or) BIOS Chip
MANUFACTURE COMPANIES (OR) BIOS PROGRAMS
SD RAM:- 84+84 168 pins two notches 3.3v
DDR1 RAM:- 92+92 184 pins one notches 2.5v
DDR2 RAM:- 120+120 240 pins one notches 1.8v
DDR3 RAM:- 120+120 240 pins one notches 1.5v
DDR-1——200 MHZ TO 400 MHZ——-having 184 pins
DDR 11—–400MHZ TO 800 MHZ——–having 240 pins
DDR111—-800 MHZ TO 1066 MHZ——having 184 pins
Types of RAM & Abbreviation:
- SRAM Static Random access memory
- Classic DDRAM classic dynamic RAM
- FPM DRAM Fast page mode dynamic RAM
- EDD RAM enhanced dynamic RAM
- CDD RAM cached dynamic RAM
- VRAM video ram
- EDO RAM Extended dynamic RAM
- BEDO RAM Burst external data output ram
- WRAM Windows ram
- SG RAM synchronous graphic ram
- DDR RAM double data rate ram
- RD RAM Rambus dynamic RAM
BLOCK DIAGRAM OF THE MOTHERBOARD
MANUFACTURE COMPANIES (OR) MOTHERBOARD
The clock signal first comes to the CRYSTAL after then it goes to the components.
The south bridge has one analog crystal.
The clock IC is rectangle type it will manage the clock signal to PROCESSER section, RAM section, and NORTHBRIDGE section.
The SOUND IC is managing the sound signal only. It is a square type IC and minuscule IC in same of the motherboard SOUND IC also given the one CRYSTAL.
The LAN IC is some of the motherboard RECTANGULAR and same of the SQUARE motherboard type. In the sum of the motherboard LAN IC near also, CRYSTAL is given.
AT power supply
Power good signal
- +12 V
Pin no Voltage
- +3.3 V
- POWER GOOD
- POWER ON
Pin no Colour
IN VIA CHIPSET SIS also
IN INTEL CHIPSET
PS/2 TROUBLE SHOOTING
Keyboard & Mouse is not working (or) PS2 port is not working.
Check: – The keyboard and Mouse are working are not. After checking the Capacitor, Coil and Resistors working are not. Next verify the continuity.
Dry solder the components replace the PS2 connector it will be working.
Serial Port TROUBLE SHOOTING
The modem is not detecting (or) serial mouse is not working.
First check the capacitor or capacitor pack working or not. Verify the continuity up to SERIAL IC finally replace the serial IC little heat serial IC in working and over heat will be serial IC not working. Then check the SERIAL IC.
In some of the motherboards
VGA PORT TROUBLE SHOOTING
The display is not coming. Check the another VGA card display is coming. Now you can check the capacitors, coils, resistors, and transistor. Now verify the continuity. Dry shoulder the components. Still not working finally replace VGA connector.
By using USB port, we can connect up to 160 devices
USB PORT TROUBLE SHOOTING
Pen drive is not detecting go to BIOS setup and check the USB port in enable or not. Verify the usb drivers installed or not. Now check the +5v incoming or not. In the USB port first pin checks, the capacitors and resistors are working or not. Next verify the continuity. Finally, replace the connector.
LPT PORT (Line Printer Terminal)
LPT (PORT) TROUBLE SHOOTING
Dot matrix printer is not detecting. Go to BIOS setup and check the LPT port is enabled or not. Verify the resistor packs working or not. In this mostly 99% resistor pack problem coming. Dry shoulder the resistor packs. After dry shoulder, also it’s not working. Finally, replace the LPT connector.
SOUND (PORT) TROUBLE SHOOTING
The sound is not coming or little volume in coming.
Small volume:- is coming that is compulsory dry shoulder resound section components before that. Still it is no volume. After change the sound IC.
The sound is not coming: – Check the sound drivers in correctly installed or not. Sound drivers are successfully installed still the sound is not coming replace the sound connector.
LAN (PORT) TROUBLE SHOOTING
The Internet is not coming. It’s checking the LAN settings still check the LAN cable is working or not. Check the LAN drivers incorrectly installed or not.
Not:- LAN IC problem LAN drivers are not installing check the continuity to the LAN IC. Minimum 4 pins worked or not still the problem is not solved replace the LAN connector.
LPT1 ( local printer terminal/ parallel port)
|Mother board side Printer SIdeOut inOut InIn outIn OutIn out In OutOut inOut InIn outOut IinIn out|
Pin no signal description
2 to 9 data signal
12 paper end
14 auto feed
18 to 25 Ground
Midi or Game Port:
1)+5V 6) Joystick 11)joystick direction
2)joystick button 7)joystick button 12) out
3)joystick direction 8)+5v 13)joystick direction
4)the ground 9)joystick button 14)MIDI in
MIDI ——Musical instrument digital interface
MIDI is the language spoken among musical instruments and computers.MIDI is not audio signal, multimedia presentation that gives MIDI are more professional sounding and easier to create. They also are more efficient because the file sizes are smaller and therefore require less resolves to press the data. The PC needs a MIDI interface to translate MIDI data to binary data.
Normally a MIDI interface is available with sound cards.
- Pin SATA Data Pin Out
Pin number Signal name
1 DV1 Digital video interface
2 DV1-1 Digital video interface- integrated digital &analog
3 DV1-A Digital video interface — analog
4 TMDS Transmission Minimized differential signaling
DVI TO LCD MONITOR
Pin no signal
- TDMS Data 2-
- TDMS Data 2+
- TDMS Data 2/4 shield
- TDMS Data 4+
- TDMS Data 4-
- DDC clock
- DDC data
- Analog vertical sync
- TDMS data 1-
- TDMA data 1+
- TDMS data ½
- TDMS data 3-
- TDMS data 3+
- Hot plug detect
- TDMS data 0-
- TDMS data 0+
- TDMS data 0/5 shield
- TDMS clock +
- TDMS clock –
C2 Analog Green
C3 Analog Blue
C4 Analog Horizontal sync
C5 Analog Ground
34 pin floppy disk drive pin out
Pin number Description
- Standard density
- In use /Head loan
- Drive select 3
- Drive select 0
- Drive select 1
- Drive select 2
- Motor on
- Write data
- Write gate
- Track 00
- Write protect
- Read data
- Side select
- Disk change/Ready
40 pin IDE connector
Pin number Signal function
- Data 15
- Data 0
- Data 14
- Data 13
- data 12
- data 3
- data 11
- data 4
- data 10
- data 5
- data 9
- data 6
- data 8
- data 7
- I/O Write data
- I/O read data
- I/O channel ready
- Un used
- DMA acknowledge
- Host 16- bit
34 passed diagnostics
37 Host chip select 0
38 Host chip selects 1
39 Drive Active
SMPS (Switch Mode power supply)
ATX SMPS 24 Pin Connector Voltage
- +3.3v 3.3v
- +3.3v -12v
- Ground Ground
- +5v Power on
- Ground Ground
- +5v Ground
- Ground Ground
- Power good (+5v) -5v
- Standby (+5v) +5v
- +12v +5v
Orange – +3.3v
Red – +5v
White – -5v
Yellow – +12V
Blue – 12v
Green – Power on
Violet – Power good
Ayash – Stand by
Black – Ground
28 pin connector voltage (24+4only)
Before power on the SMPS Circuit
Standby voltage +5v and power on voltage +5v is coming to the power connector.
After power on the SMPS circuit
The power on voltage becomes to “0.00” and reaming all the output voltage comes to the power connector.
Intel 845. Motherboard Power section “BEFORE” Power on the Motherboard
- Intel 845. Motherboard Power section “AFTER” Power on the Motherboard
- SQUARE BIOS
- 1pin is dummy pin2pin is reset voltage (+2.5v to 3.3v)32pin is primary energy (+3.3v)31pin is clock signal (1.2v to 1.6v in multi miter)5to 13pins and 30 pins, 3pin 4pins there are address pins 14th to 29th pins theses all are data pins845 Motherboard power section before power on the Motherboard
- Standby voltage +5v and power on voltage +5v is coming to the power connector.
- Standby voltage is given to the One transistor.
- Transistor input voltage is (+5v) and Output voltage I (+3.3v) and (2.0v).
- Two voltages is given to the register through the ground.
- 3.3v is given to the “COMS” jumper setting nearest capacitor the capacitor shows +2.9v to 3.3v.
- 3v is given to the SOUTH BRIDGE closest one capacitor more than one capacitor also shows +3.3v it is working but at lost one capacitor shows 3.3v then SOUTH BRIDGE is working fine.
- Standby voltage +5v is given to the power store pin nearest capacitor. Through that capacitor, the +5v is given to the power start pin.
- The power on voltage +5v is given to the SMD IC nearest capacitor through this capacitor the power +5v is given to the SOUTH BRIDGE most adjacent crystal in multi-meter it shows 0.2v to 0.9v.
845 Motherboard power section After power on the Motherboard
- The power voltage becomes to “0.00.”
- The power good voltage +5v is given to the “SMD IC.”
- The SMD IC input voltage is +5v and output voltages are +3.3v, +2.5v, +5v, +1.6v or +1.8v.
- The square BIOS primary voltage is +3.3 it shows at 32pin.
- The square BIOS reset voltage is +2.5v to +3.3v it shows at 2pin.
- The square BIOS clock signals voltage is shown in Multimeter 1.2v to 1.6v at 31st pin
- The CLOCK IC Main voltage is 3.3v and clock signal voltage is shown in Multimeter 1.2v to 1.6v
- Southbridge and NORTH BRIDGE Main voltage is +3.3v and reset voltage is 1.6v to 1.8v
845 Motherboard PROCESSOR SECTION
845 Motherboard “RAM” SECTION
DDR 1 RAM SLOT VOLTAGE
Ram Voltage +3.3V (92pin)
Reset Voltage +2.5V (Notch beside 2nd pin)
Data Voltage 1.2V to 1.6V (1st pin)
Any Motherboard PCI slots voltage is same.
In same of the boards IED port, all tracks are given to the South bride. Directly or through resistor pack. Conduction
TROUBLESHOOTING NO POWER CONDUCTION
NO Power or Motherboard is not power is not power on.
- Check the standby voltage and (+5v). And a power on voltage (+5v) is coming or not in the power connector.
- The standby voltage is given to the TRANSISTOR or FET, or VOLTAGE IC.
- Check the input voltage output voltage of the components (FET, TRANSISTOR) input voltage is +5 output voltage
- Check the CMOS Jumper setting is properly connected or not and check the voltage of the jumper setting (2.9v to 3.3v)
- Check the south bridge nearest (3.3v)
- Check the power start pin voltage (+5v) in the same of the motherboard voltage (3.3v)
- Check the SMD IC input voltage (+5v)
- Check the south bridge nearest CRYSTAL in multi-meter it shows (0.2v to 0.9v)
- Check the processor section (12v) FET is not working then processor FAN is one siècle it will be rotating and stop.
- Check the north bridge and south bridge nearest capacitors.
- Check the LAN IC is short or not.
- Check all the motherboard FET and POLARIZED CAPACITORS was working or not.
- Check with another BIOS the motherboard is on conduction that problem
- Finally replays the SMD IC
SYSTEM AUTOMATICALLY HANGING OR RESTARTING OR SHUTDOWN.
- Go to BIOS setting and observe the same time in BIOS setting.
- In the BIOS setting the system is hanging or restarting or Shutdown that is the hardware problem.
- In the BIOS setting the system is not hanging or not restarting or not Shutdown that is the software problem.
HARDWARE PROBLEM SULSTON
Showdown, Restarting, Hanging.
- Check with another SMPS.
- Check with another RAM.
- Check with another processor FAN.
- Check with another BIOS.
- Verify the processor section and RAM section voltage.
- Check all the polarized capacitors is working or not.
- Check the BIOS voltages and CLOCK IC voltages.
- Check the south bridge and north bridge main voltage and reset voltage (1.6v to 1.8v)
Board on condition but no display.
- Check the monitor is working or not monitor is working is fine.
- Check the COMS jumper setting is correctly connecting or not.
- The jumper setting is the 1 and 2.
- Clear the BIOS setting.
- Check the RAM and RAM slots are working or not.
- Check the SMPS all the voltage is coming correctly or not.
Note:- All the voltages are coming except power good then board is on but no display.
- Check the processor is heating or not.
- Check with another processor FAN.
- Check the processor section voltages and RAM section voltages.
- Check with another VGA card hear the display is coming than that is the VGA port side problem.
- Check with another VGA card also till the no display.
- Check the BIOS voltages and another BIOS.
- Check the CLOCK IC voltages.
- Check the SMD IC is an input voltage output voltage.
- Check the southbridge and northbridge voltage.
- Check the entire board FETS or POLARIZED capacitors is working or not. (northbridge problem)
915 Motherboard Power section “BEFORE” Power on
915 Motherboard Power section “AFTER” Power on
915 Motherboard Processors section.
- 915 Motherboard RAM section. DG31 MOTHERBOARD “BEFORE” POWER ON THE MOTHERBOARD.DG31 MOTHERBOARD “AFTER” POWER ON THE MOTHERBOARD.DG31 MOTHERBOARD PROCESSOR SECTION. DG31 MOTHERBOARD “RAM” SECTION.
- Hardware Troubleshooting Pc Boot Problems: (beep codes)
indicator system status no beeps – no power loose cord, or short. 1 short beep – normal post computer is ok. 2 short beep – post error review screen for error code. continuous beep – no power loose cord, or short. repeating short beep – no power loose card, or short. one long and one short beep motherboard issue. one long and two short beeps video (mono/VGA display circuitry) issue. one long and three short beeps video (VGA) display circuitry. three long beep keyboard / keyboard card error. one beep blank or incorrect display video display circuitry.
Problem With Power Supply Or CPU Chips: make sure the power connector is connected correctly and fitted firmly in the motherboard socket, some motherboards require two connectors from the power supply, refer to motherboard manual. if the problem persists try using a different power supply. check CPU fan, remove a chip and clear dust, make sure it is mounted properly. Video Card Problem: remove video card and inspect for cracks or bad connectors. make sure the video card mounted correctly in the slot, try using a different video card.
- DMA Direct memory access
- PGA pin grid array
- BGA ball grid array
- FDD Floppy disk drive
- CGA color graphic adaptor
- VGA video graphic adapter
- AGP accelerated graphic port
- PCI peripheral component interface
- ISA industrial standard architecture
- MCA micro channel architecture
- EISA extended industry standard architecture
- CMOS complementary metal oxide semiconductor
- BIOS basic input output system
- USB universal serial bus
- MIPS millions of instructions per second
- MBPS mega bytes per second
- SMD surface mounted device
- IRQ interrupt request
- IBM international business machine
- AMD advanced micro device
- SIMM single inline memory module
- DIMM double inline memory module
- RIMM rambus inline memory module
- AMR audio modem racer
- CNR communication network racer
- ACR advanced communicated racer
- NIC network interface card
- LAN local area network
- ATA advanced technology extended
- FWH firm ware hub
- AT advanced technology
- UDMA ultra direct memory access control
In server side used 94 pins
Pin number Signal
Pin number Signal
- 1 -12v
AGP Bus connector
+12 V——–pin no 1
VCC ——–pin no 9,16,28,45
GND ——- pin no 5,13,19,31,37,43,49,55,61
+12V——pin no 16
+3.3v —–pin no 18
+5v —–pin no 19
GND —–pin 3,6,9,14,17,20.
Mother board spare parts numbers
Alpha AS 2830
3 LEADS — AMS1084
5 LEADS—–E31FG UNISCAN
- CETCEB 60302CET60NO35CETL31035NECK3296PHB 55 NO3LAAPL LO85F37115F37045MTB 1306MOR OCCO 3620L55N FO5L
GD 75232 (P-III Boards)
St 75182 ( Old boards(12v)
Mini voltage IC
MIP 6008 CB
8 PIN IC
ADP 3148 K
AT 82C58 VP
TTL IC 14 PIN
LX 1662 CP
W8 3697 HF
W8 3637 HF
W8 3977 EF
HIP 6019 DCB
HIP 6020 CB
US 3007 CW
US 3004 CW
Limifinity LX 1665
Unisem 3004 cw
Unisem 3007 cm
Supplies in Mother Board spare parts
+3.3v +5v +12v -5v -12v
PCI Key board PCI ISA CNR
AGP Mouse AGP
CNR USB CNR
SMD IC Game port CPU fan
Southbridge VGA 8 pin IC
RAM slot IDE
Crystal IC south bridge
BIOS (basic input output system)
Features of BIOS
- CPU support
- Chipset support
- Memory support
- Power management
- drive support
- PC 2007 operating system support
- Boot versatility support
- parallel port supports
- plug and play support
- PCI & AGP support
- USB support
- Antivirus support
Beep codes for general identifications
- one short beep when display logo
Solution: no error during POST ( power on self-test)
1. long beep in an endless loop
Solution: NO RAM installed or RAM not detected
2 One long beep followed by 3 short beeps
Solution: video card not detected or not found
3: High-frequency beeps when system is working
Solution: CPU overheated system running at a lower frequency.
PHOENIX BIOS BEEP COEDS
Beep codes Problems
1,1,3( short) CMOS chip
1,1,4(short) BIOS failure
1,2,4(short) mother board
1,2,3 (short) mother board
1,3,1 (short) mother board
1,3,4 (short) mother board
1,4,1(short) mother board
4,3,1(short) mother board
1,4,2(short) memory module (RAM)
3,2,4(short) key board controller
1,2,1 system time error
2,,x,x(short) chipset error
3,3,4(short) video adaptor problem
4,2,4(short) expansion card failure
4,3,4(short) time of day clock failure
4,4,1(short) serial port error
4,4,2(short) parallel port error
4,4,3(short) co processor error
Standard IBM BIOS Beep codes
Beep codes Problem
No beeps power supply or system boot failure
One short beep post is ok
Two short beeps post error with error code display on a screen
Repeating short beeps power supply or system boot failure
1 long & 1 short beeps system boot error
1 long & 2 short beeps video display adapter failure
1 long &2 short beeps video display adapter error
3 long beeps keyboard error
AMI BIOS Beeps codes
Beep codes Problems
1 short beeps post is ok
2 short beeps memory failure
3 short beeps memory or parity failure
4 short beeps system time failure ( the system clock timer
chip has failed)
5 short beeps motherboard failure
6 short beeps keyboard controller failure
7 short beeps CPU failure
8 short beeps video adapter failure
9 short beeps ROM BIOS check some error
10 short beeps CMOS read& write error
11 short beeps cache memory error
1 long, 3 short beeps memory failure
1 long, 8 short beeps video adapter failure
Award BIOS beep codes
Beep codes Problems
1 long beep memory error
1 long, 2 short beeps video error
1 long,3 short beeps video failure
Continuous memory or video failure
PROCESSOR SPEED & OPERATING VOLTAGE
Model Processor type CPU speed Voltage
Intel 486 sx,486 dx, 66 MHZ,100MZ 5V,3.3V
AMD 486 DX, 486 DX4 100MHZ 3.3V
Intel P-1 old 75 MHZ to 133MHZ 3.3V
p-1 166MHZ to 233 MHZ 2.8V
IBM P-1 pro 200 to 333 MHZ 2.9V
AMD P-1 K6 350 to 550MHZ 2.2V to 3V
Intel P-11 266 MHZ to 350MHZ 2V
Intel P-111 400V to 1.2V 7V,1.6V
Inetl P-1V 1.5 GHZ to 2.7GHZ 1.6V
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