Troubleshooting Hardware and Storage Devices Flashcards
Troubleshooting steps
- identify the problem
- establish a theory
- test the theory
- establish a plan of action
- verify system functionality
- documentation
causes of power isssues
- power button not connected to motherboard
- wall outlet faulty
- power cable to computer faulty
- power supply faulty
- power cables from power supply to components faulty
- incorrect voltage setting on PSU
wall outlet faulty
use multimeter or voltmeter to test
- 110-120 in usa
- 220 in rest of world
power cable to computer is faulty
disconnect cable, take multimeter, and run resistance check 3 times, ohms should be zero if working fine
power supply is faulty
12V, 5V, 3.3V
- use power supply tester
power cables from power supply are faulty
use multimeter, check each pin on each cable
incorrect voltage setting on PSU
- older servers/PSU
- switch on back of PSU
POST
diagnostic program inside system firmware
1 short beep
normal POST - system is OK
pinwheel of death
Mac
- unresponsive apps
Kernel Panic
linux
- black screen with white text on it
- system display gives exit code
BSOD
- windows
- problem with underlying hardware
cooling issues
- fans working at high speeds
- randomly turning off and on
- feels hot to the touch
- overheating into OS = app problem
system overheating
- shut down system
- boot into UEFI//BIOS
CPU overheating but fan working ?
thermal sink issue, take off heat sank, add thermal paste, put it back
rancid smell
blown or burst capacitor
inaccurate date time
battery failing on motherboard to keep RTC in sync
CMOS
non-volatile type of memory that stores BIOS settings and built into motherboard
NVRAM
stores data without being constantly refreshed
- more modern version of CMOS
what is problem if computer won’t boot but fans keep spinning
power supply, overheating, or motherboard issue
inability to find bootable device, OS not found, invalid drive spec
problem with boot sector
bad sectors solution (HDD)
use disk utility like chkdsk
SSD bad blocks
use spare blocks at end of device
SMART
self diagnostic program that alerts OS if there is a failure
- monitors hard drive and understands health of drive
- IOPS = lower on HDD
