Monitors , Displays and Screens , problems (solving them)   

See how , Sleep mode or hibernate mode or screen savers can fool you, see why and the cure , here.

There are many screens,  used for ages,  CRT (cathode ray tubes; Legacy),  Desktop LCD then, LED , and LCDs inside Laptops (notebooks) both CCFL or LED back lighted.
Index: (failures)
Desktop LCD
Laptop screens
Solder balls from H3LL
The Flash light test.
Inverter failures CCFL
Desktop Inverter

DISPLAY's & Monitors & Screens 101: (do not read this history / facts jump to fixing it now)
A very complex topic and scope, history and evolution.
In the dark ages of PCs, (in the 20th Century, yah) we had CRT, Cathode Ray Tubes, just Like Karl Ferdinand Braun did in 1897 just now  (modern) we have  color and huge complexity. (yes, a huge VACUUM tube = CRT)
IBM sold the first PC 1991 with a MDA CRT monitor, the EGA later.
They are now gone,   (they lasted for 100  long  years and are dead technology now) RIP! 
LCD is used both on Desktops and Laptops (LT)  the screen is the same but not the CCFL parts, nor are the driving electronics the same.
The Desktop has its own power power supply card, its own inverter ,screen and its own VGA decoder, all inside the monitor. (plus a OSD brain  (year 2000+?) that no  LT has)
The laptop has  screen and CCLF or LED back light and its own special video chip to drive it directly (bypassing VGA totally) see the table below for some Devices with CCFL tubes inside.
The chip in the LT drives the LCD matrix direct driver chip. (most LT have and AUX, VGA port,or HDMI  on new LT)
That super old 2002 (?)OSD menu, has a Power Saver there (INSIDE IT), (turn it off for sure or go batty, we use VESA modes today Via PC commands)
See super short history here.

The PC must ask (PnP logic) the display who it is (what are you?),  as the OS boots, and the display tells the OS what is there and the rules to use it , if not?, bad happens. (like out of range errors)
PnP or Plug and play (pray?) must guess or get right the monitors resolution legal ranges,  for sure the max resolution and if PnP guesses wrong (setup files missing) it can  cause any screen to go dead or worse get ugly.
On some old CRT getting this wrong you can burn a hole in the screens phosphor dead center. (not using the "multi-sync" rules as it stated back then "dark ages of CRT")

Next is "Energy-STAR" and VESA rules.  (wiki it) But all screens near the year 2000 up have this.  (and works in different ways, if you do not know how this works you may be fooled by it.)
Then the new VESA standards added PC commaded sleep modes. (and is related to PnP, plug and play, the OS must know what display is there or it can not set the correct resolution mode.
Odd duck old screens (circ 2002 year)  See more here...
The very old screens (external) had a sleep timer inside , near year 2000 and after 2004 all had sleep modes now located in the PC and the DISPLAY SLEEP timer (Desktop)was deleted.
The sure is easy, push the display front panel menu button and turn off the SPEEP/Power saver timer now.

When you boot any PC the OS sends out PnP commands for what screen is there, using PnP (PCI) messages, if no answers come back PnP fails, if it comes back and the message is so old that Windows can not support it, then it fails. (one way to get past here is use Window SAFE MODE)

The GPU card or chip (and friends) could force sleep now, simply by disabling  either of the 2 SYNC lines to the Display,  (they changed the rules 4 times, to make all this fun) (not)
The screen errors are all true and real,  it can show (monitor brain did this, not the PC ever)  (these are all OSD brain transmitted to the screen of only desktops.)
  • "NO SYNC" errors.  means the horz/vertical sync lines in the cable are dead. (PC issues)
  • "NO signal" means Video lines in cable are dead. (PC issues)
  • "No connection" errors means all lines are dead, in the cable.

The LCD matrix , is not a light emitter like CRTs were, it is only a contrast device.  (thus the background lamps used)
 (that means it can not glow ever, like say a true OLED panel), most screens Tagged as LED are really only a LED back  lighted LCD, so the user can see what's on the LCD matrix before you.
These CCFL BULB's seen on most  old PCs (and monitors) are Florescent lamps that LOVE TO FAIL, from  5 to 10 years old. (cold cathode fluorescent lamp) or get ulgy yellow or go dim.
The maker tube claims 20,000 hours or 2.2years run full time)  pathetic for sure...
This bulb tube is called a  CCFL. (they love to yellow too .see CCFL comments below..)
(LED back lamps can last near forever, near 20k hours, I have LED clocks that are 42 years old and still run like day 1)
The display or Laptop has 2  dim buttons (up/down), if set low, the screen can be too dim, (obvious) but not so obvious is the button on a laptop needs a special driver to make this button work at all. (and the HP control panel DRIVER to match it.)

The CCFL goes dim  and somethings we push the up button to full brightness and bingo in a dark room, we see a working display  , but useless, unless you are in a dark room. (a classic CCFL device failure)
 (if you upgrade the OS this can cause this GPU driver to fail, easy, so use only correct matching HP disks or matching HP drivers seen on HP.COM to upgrade or reload the HP full OS, Operating System)
WINDOWS also Auto dims displays too, on all laptops made,  new out of the box the Control panel + Power settings, if you look all  go  to dim mode, when on battery, so you can turned off this FEATURE. This FEATURE is to extend battery life, while on battery.
Windows also, DIMS the display on battery mode operation or if say on battery mode, the power levels are too low. (weak battery) this is to make the battery last longer, its a FEATURE, if you don't like that , turn it off.
(Windows, features that can effect this are, Sleep, Hibernate,screen saver and low battery modes) All of these can cause you a problem. (The windows control panel, power settings is the place to look first)
Some newer PCs have a auto-dim that dims the Background lamp, with a dark room and the reverse is in bright sunlight, using a magic photo cell, device, to measure said background light or uses the WEB cam  to do that.

Like most things in the real world , most things can be good, bad or dim.  (weak, intermittent or acting very odd)  GOOD bad or shades of gray... (the universe is analog , not digital)
The CCLF inverters also LOVE to FAIL as  do the tubes  
The inverter converts low voltage  to high voltage that the CCFL needs in order  to glow CCFL. 

Diagnosis is very simple, in most cases, the first test, if the screen is black all the time power on, is use a Flash light. 

If you see the below, see BIOS, or Windows login, the screen really is not dead, is it?  only back lamp issues.
Also if using a screen saver, (don't) this too can cause problems.
Clues common:, monitors power button goes yellow or orange not green, the Screen pops up a message (OSD brain inside did that) and says, lost sync, NO SIG, or Sleep mode, or power saver mode.  All mean the PC did that on purpose, in most cases.
If the Displays OSD is dead, the monitor is dead, or lost power. The Menu key on all desktop monitors must work, or power is lost or the monitor is now DEAD.
Sure a bad monitor cable can do this.  sure. (but will not kill the OSD)  If 1 SYNC line breaks the monitor goes to sleep mode. VESA rules, tell you all these facts.
A laptop has no OSD brain or menu's, so just goes black for sleep mode.  I pound the space bar to take a PC out of sleep or deep hibernation,.. can take 3 minutes to wake it up.
A laptop can use the External VGA port,  15pin D-shell and to use said jack on HP, hit the Fn+F4 key pair, and pick external, both or auto mode. This is test #2 after the flash light test.

Top fails: (first are old screens, with CCLF)
(for sure if OSD screens are dead)  OSD is only found on desktop monitors., if BIOS is dead, this can be it)
CCFL is old school Cold Cathode Florescent lamps.  (with a 2.5year shortest life span possible, most go 2 times that easy) No LED fails this fast, none.
That love to go bad or dim and turn yellow,  newer LED back lights, new Displays just keep going, like a Timex watch. 
For most OLD LCD displays, that fail for this , the cost for the parts alone (labor omg more) is more than this old LT/or monitor is worth...
(but you can connect any external VGA screen and use that, and abandon the internal LCD screen.
 Walmart has  nice $50 display for sale, why not upgrade to LED display now.?

Top failure modes:  (the fast quick tests are here) In all cases if the screen is not totally dead, hit the home button above,  or see windows is dead page here)

Desktop: DT monitor   (when I say VGA port or cable , it means that or DVI or HDMI what ever you have connected for video to this monitor)
  1. Monitor is not plugged into wall jack AC or the monitors LCD  power pack is  dead.
  2. Not turning the power button to on (dah). (or the home/room fuses are blown /tripped  or neigborhood is in a black/brown out?)
  3. OSD lets you set brighten or dim screen levels so... (hit the display menu key button (front of monitor)   if OSD menu's are  dead, then the monitor is dead) OSD means "On Screen Display" Feature.
  4. OSD errors, seen live as the PC boots (no sync/no signal/connection, are all PC signal failures that mean the PCs VGA  port is dead or the PC is dead in some way. See black screens here.
  5. The display LCD-CCFL is dead weak, or its PS_inverter and you can prove that in 1minute flat with the flashlight check below.
  6. The VGA cable  can be bad, test it.  Best is to test this monitor on another PC of any kind. (with same jack) or test the PC on another Monitor, or if PC has HDMI test the PC on  HDMI ported TV (television)
  7. When tje PC dies the monitor told you it dead with clear errors shown there,"no sig, no sync, no  connections" PC dead is here. (black screens of death)
  8. The monitor may also show ("im in sleep mode or power saver mode" in most cause this is the PC messing up. or the rare case of old 2002? monitors  , the super secret internal timer.

Laptop  LT, only screens.  ( lots more to fail here, due to more parts in play and shared power !) 

  1. A :Laptop battery bad (shorted)  overloads the power supply regulators a , take out the silly battery now please and retest it now. (what could be more easy,  on real laptops) (some notebooks harder with hidden batteries)
  2. The laptop needs a good power pack 19vdc  we test it with a voltmeter or try another pack, it is a good idea to have 2. (over 64watts rated) Some larger LT with larger screens and very fast CPU need 100watt packs.
  3. If the LT fails to show BIOS screens or text ever, at all , then see flash light trick below, of that fails then  see this page on total 100%  black-screens of death here.
  4. The LT dim keys are fn+F10 set (low), I  push   fn+F10 UP and go to full brightness, a weak/bad CCFL will caused dim or dead screens, so is a CCFL failure. (on my LT the dim/bright hot keys also work under BIOS too.)
  5. If  the OP-.system display drivers and or the HP keyboard (dimmer) drivers are missing wrong or corrupted or infected , reload windows.
  6. The display LCD-CCFL is dead/ weak, or its inverter and you can prove that in 1 minute flat with the flashlight check below. (you also ? discover that Test 7 below works)
  7. The external monitor connected to the VGA jack on the rear, that fails (fn+f4 key)means the GPU is dead, or the PC is dead.  This must work externally even with BIOS pages work here, or the PC is dead.
  8. My screens all work even with HDD removed, and DVD drive ot, and even with 1 stick of memory alone. (there are my modules inside that can short, but all that is in the black screen of death page..)
  9. The first rule is always get the BIOS screen working as seen below.
  10. Do not skip the test 7 as this can be a VGA jack or HDMI port you can use to test the LT for functionality. Some LT need this part to do the external tests.
  11. The LT inverter card can fail, the cables can fall off inside to LCD panel, Before condemning any screen we do the flash light test and check the cables, even re-SEAT them. (we do BIOS screen tests hitting ESC key)
On my HP 8540w LT the fn+F10 even works in BIOS, even on the BIOS  info page this works, but if it fails in windows only, the HP Quick launch button driver is missing, SP49104.exe from HP. (mine only)
The DRIVES must match your exact PC and your Loaded OS (w7 , 8 or 10)
Note carefully Microsoft updates do not work here for this Quick Launch software even in device manager,a  forced update fails.
This is just one example, so you must find your drivers (all) at HP matching your PC and your OS.
Watch out for PCs that do not support W10, and all these fancy dancy driver are missing and not supported by HP (if true) nor by Microsoft. (mine fails on all  HP security software features sets, so I don't use them with W10.)

Anyone can do this. "The flash light trick"

I take my flash light, and point it to my black dead screen.  (I am hammering the ESC key, "flashlight pointed to screen, power on and quickly hammer the ESC key" BAM BIOS POPS.
or if you know windows is running, you heard it make music, ? or just  know it by the sounds of the HDD etc,,, then just use the flashlight, now. BAM, yah, got  DATA?
If I  see data here, this is BIOS but can be Any windows screen of any kind ,or even a login screens or BLUE SCREENS 's. See, it's not dead is it; only the Back lamp is DEAD, (and must be replaced)
This is the first CCFL test. (mostly before year 2010 PCs)
      what could be more easy? Omg the data IS THERE !

When I see the above, (I have repaired many )  but I can  get this Desktop  monitor from walmart for near $50 and use it.  or a whole PC for  way  less !!
One can use a Desktop screen on your laptop in  pinch or at any time. (mobility here will cost you way more,  labor and parts.
All HP LT have service book telling you the steps to remove this screen and put back the new one. (some LT have no separate inverter cards but deep planted the display."hidden")

But if portable is necessary, then you must fix it, and below that is what I am doing.... (some just use and VGA external monitor for , cheap cash used and use  that forever)

Keep in mind that the LCD connector migh just fall off, for sure if monkeys played here before and did not put back the tape to secure it like new.

One more inverter fix, in a very different way below is a LED CONVERSION kit.  I've done a few. $100 fix to.... so... you must either be rich or crazy like me, ..
If all you need is an inverter ?, ebay has them used for about $5 (the tubes can be changed but is not easy, youtube that, to get the level of difficulty , step one is remove the screen.)
Here I am upgrading the CCLF screen to LED Back lamp screen, see the new Inverter dead center. (the screen was cracked and wrecked,  so I upgraded it)
The new , Genius level inverter here fits vast numbers of laptops. The extra connectors do  that.  (this is a Toshiba.)

this HP logo is BIOS generated, even if HDD is missing.
This  is NOT A dead screen for a fact, at all ,see the HP logo? , these TEXT words from BIOS?  this is not a dead screen and BIOS is not dead. To prove that, hit ESC at power on, see it is  not dead.
 (hit the home button above if your screen is not truely dead.)
 See why WINDOWS IS DEAD. or see windows is dead page here)
Windows has vast modes of failure, It's like a dirty sponge , rinse ,wash and repeat.. Windows can even boot over and over endlessly, or stick on the spinning bullets ICON or even have a dead login screen , looks ok but is dead.
All  lost passwords are here.


Solder ball H3LL: CIRCA 2008.  (newer PCs just ignore this) lead free year, horrors.  (this horror is a mix of bad design and allowing the PC to overheat)
This is a surface mount device, SMD, and uses solder pad/balls, If you look at it, you learn in 1second flat it's not easy to fix at all.
 (I will demonstrate this using a better LT PC, one that has  totally modular , VIDEO CARD)
(this can cause a range of wild and crazy symptoms, and for sure  intermittently and screen acts crazy, as the  LT base is flexed.)
One more clue is the rear VGA  jack fails (using an external monitor), too when the PC is flexed,  (GPU failures do that)
 The 2008 era, LT have the GPU solder ball failures from H3LL problems cause by the USA Federal mandate of lead free solder, laws.{think Monkey wrench effect}  (yup, it was born dead, complex thermodynamic reasons, low melting point solder) 
The are 3 reasons for this failure, 1: not putting a steel stiffener frame on the MOBO, 2: a bad  brand of new Lead free solder, (too low melting point) and at the same time, if lap top vents are blocked you can overheat the GPU easy,
Some solder melts at 136f (58C)  not saying this was used, only saying they used the wrong solder,, my bench solder sn63 melts at 183C
Some users placed their laptop on a blanket , it overheats and the solder here was damaged. (like perfect storm, but is now cured)
Also some PC overheated fast and easy. (some LT makers just hid the problem by running fans full time or 2 times faster all the time) (preventing many dead displays)
If sitting on a beach at 120F in the shade, and the LT goes dead, are you surprised? Most will overheat like this and worse if the sun lands on the LT.
One LT, if you press hard on the J key  , the  GPU bad solder balls, connect and  the screen wakes up, or goes dead. (yup).
Or,  remove the key board and press on top of the GPU chip now,  does the screen wake up now? BINGO? bad solder joints you HAVE! (kiss off one MOBO) but not mine below, it's an Elitebook.

My GPU unplugs. (GPU means Graphic Processor Unit, or chip)  Yes the chip runs hot, and has heat sinks, as do those fast RAM chips seen here.
The large chip below is it, and will overheat if the heat sink is missing or fell off.  (loose or the thermal compound is cracked)
The other chips are dedicated RAM for the GPU. The RAM chips on mine have heat sink pads. 1mm thick (I reverse engineered them, 2 ways, the pad them self and the gap measured.)As seen here.
Do not let hacks fix your PC or they many make it worse not using proven heat sink compounds or pads, the correct thickness. 
Warning 2,  I see laptops failing for GPU too hot, I then check the heat sink and find that the compound is now hard as dried clue and brittle,  and is now CRACKED from natural LAPTOP flexing.  What ever they used there for compound is NO GOOD. I use this.

My Graphics screen driver CARD: below:  (HP Elitebook 8540w)  My LT has 3 card options. (speed)
I love only Laptops that have a card that unplugs, (you do get what you pay for here!!). (not only that, but I CAN UPGRADE IT for gaming, or for CAD/CAM or for Video editing extreme. Yes, PCs are versatile.)
Some cards sell for $20 used.  (what a deal and not one has Solderball problems !)
The solder balls (SMD) are under this big green chip below, called the GPU, graphics processor.  (the conditions of assembly here are complex, Re-flow methods in an OVEN)
It runs real hot, the better and faster the chip the more heat it expels (like gaming does),  The balls can not be home repaired,  doing a ball remelt in moms oven is 100% failure event, I can replace my card but most cheap laptop owners the MOBO is bad now.  $150 used part. or more.
This example below never ever fails for solder balls , but the photos of my GPU are very clear, and you can see no human can go under there, and fix bad balls. (only a re-flow oven might but at home is  hard fail to try)
HP 8540w, is the best LT HP ever made, I hoard them.!
The test to see if this chip is bad is press on the Keyboard "J" key the chip is below that key, on your LT the pressure point would be different, read the service book to learn that location.
or learn to twist gently the whole base of the LT.  (a bad screen can be tested the same way, twist the screen bezel, gently) see lines,? yes, then , bad a screen.
I can also remove my keyboard and then press the GPU chip to my hearts content, to see if the screen acts up.  (2008 is the year of horror for said chips)
A savvy Tech knows there are many  classes of failures, (lucky me , no hydraulics or pneumatics. here.)
  • Bad power, (always first this) (does it run with no battery?)
  • bad electronics,  (or electrics like motors are electric)
  • bad connections  (cables and jacks)
  • Thermal dynamic problems. (overheating)
  • Fans dead,  the motor in the fan dead packed in lint or hard disk drive motor is dead (silent)
See why PCs over heat, here.

NOW LEGACY HARDWARE.... (cry a river? song played now?) History and Evolution matters, it lets you know what you have before you start testing things.

CRT and CCFL are now legacy hardware.  both are now, IMO...  CCFL ALL:
Over 10 years old falls into that pit of legacy hardware, and all the bad things with it, (lack of support, lack of parts tops that list)
HP Made many CCLF Laptops, from year 1997 (first LCDs) LCD beat CRT's sales in 2010    CRT were introduced by IBM in 1991 with MDA monochrome CRTs.  (mine was amber opted)
 Later came EGA displays. (bought mine 1st day they offered it with the matching card)
I show the  history to help you know what is inside your display (or PC) and aid in trouble shooting it.  (my friend says, "if you don't know how it works?, how can you fix it?" rings true.?

The bright white LED was introduced in September 2003 by Cree, but it took many years  for PC makers to latch on too this device. (slow my guess, is was  due to LED costs in 2003 ,or near)$2 a pop is super expensive.
CCFL's ended about 2010 in Displays.(LED takeover) Just as CRTs died down fast, and for sure helped with the push over.
These tube lamps can fail, or go dim or go yellow or flicker or the inverter power supply for it is bad.
Do not forget that many old CCFL laptops you can buy a LED conversion  upgrade for many, as seen in ebay...(For HP621 / G60 / DV6 / CQ60, and more )
This table is not complete: (one trick is to pretend to buy a CCFL for you screen, if can't? then it don't have one.)
Old Laptops. CCFL  (most)  "The PCs not to buy used"
Most old  Compaq CQ series , CQ40,50 ,60 61, all made before 2010.
Compaq 6500 series  6700, 6800, 6900...  8700's
TC1000 and L2000
519-535  hp 500 series
DV2000 up to  9000 series.
ZX5000 series  , ZD8000
Compaq Nx series, nx6000? nx9400  
N600, NC8000 series
nx8200 series
DV4,5,6,7,8, series.
and lots more..G60 ,G61, G70
Very old Elitebooks had CCFL 6530s,6930s,8510,8530,  (never 8540s) (oddly my 8540p/w   all 6 screen options are LED)
I think xx30 and xx10 means CCLF inside.. Elitebooks.

Monitors with CCFL , and internal HV power board. (seen below)
L15xx series,  L1503 is common (the first 2 numbers are size wide)
L17xx series
vs17, vs19. VS15 bit VS19 is LED.
and more. 
but a warning; I saw some old names like L- Series,a monitor with LED the last year it was made and  a new power board inside to match.
The introduction of LED started with large screens at and above 20" , then moved to more narrow screens.(cheaper screens last).

Below I will show some old External desktop monitors.  (first is the PSU the power supply inverter unit (PCB) "Printed Circuit Board"
This is a  HP L1711  Monitor PSU that uses 2 High voltage jacks at left, to run the CCFL tubes.
 The silk screened words there clearly show HV Caution. Giving this lil' secret away. Almost all HP PSU that have CCLF use the same look alike jacks.(hint 2)
Note how the jacks are isolated (lots of PCB space) so that HV does not ever land on that jack to the right and blow itself to kingdom come. (they know  this PCB will be buried in dust too and dust conduits electrons) Shock hazards here.

The CCFL the cold cathode Florescent lamp below.  ( these can go dim in 2 years of continuous usage (no sleep/hibernate modes used)  LED's can go for 20 years full tilt.
This is a RANDOM CCFL TUBE.  some need 500 to 1000volts to run, varies by length of tube and dim setting.

OSD is a menu
that the Monitor Brain inside presents to you, on demand, Push the Menu button, below Mr. OSD . as seen below. The PC brain (CPU) does not do this at all.
This is a new OSD screen ( monitors brain does this not PC) (key features to try are, brightness, and factory reset and OSD lockout)
Relic , legacy monitors look like this below:. Even CRT monitors had this. (the most old CRT never did !)
circa 2000? old. On the oldest monitors say year 2000, there can be SLEEP timer here, TURN IT OFF NOW , keep it OFF.

L1703, try factory settings yet, brightness, color temperature, ? You can even custom set the RGB color levels as you like.
If you view a white screen , say in MS NOTEPAD,  and it's yellow looking not pure white, the CCFL is bad. and colors will be muddy.
To get this OSD screen push the front panel monitor button called Menu (or select).
The OSD lock feature can be turned off by holding the menu button for 10 seconds to 30s. max.
The OSD can  have  a test pattern page, so if the test pattern looks wrong, you know for  a fact the display is failing or set wrong.(read your users guide yet?)
This HP test pattern inside the HP OSD menu's is really a nice HP feature, so you can see if the monitor is ok and can be used to tune the colors as YOU see fit.
Learn that monitors made from 2000 to 2010 year, had OSD changes made (radical) for VESA and EnergyStar rules/laws. 
The classic example of that is around 2004 they dropped the internal sleep timer (I hate). (always turn off said timer  first)
For sure the video cables can fail. (try another cable yet?)

  INVERTER cards do fail, and often. (or the lamps ) 
Many CCLF screens have an out-rigger Inverter board that converts,  5vdc? to 500vdc. for the CCLF tube to Ionize and glow.  The Desktop monitor inverter likes to  hide  here.
The tubes love to fail or go dim, yellow or flicker, and so does the below love to fail. Buy them used on ebay.
Some Inverters are buried deep in the screen where no man can go or worse can't buy them at all , only a new screens cures this.
See the old DV2000 inverter its really a DC to DC converter, low volts to high voltage (and can shock you playing with it)

CRT's;   the CRT needs a trip to the  Recycle center  fast.
A working CRT is amazing today. Most of them are dead or the RED GUN is way low, (can be raised in the Menu's of most.)  If the CRT fails , most parts are not found today... (good luck source relic legacy part like this)

version 1.  7-29-2017   (no PC diagnose here this is only MONITOR or screen failures)