Screen inverter board
Laptop inverter boards (also know as LCD inverter, FL inverter, screen inverter, backlight inverter) come in different shapes and sizes. On the picture above you see some typical looking inverter boards found in laptop computers.
The inverter board works as a power supply for the backlight lamp mounted inside the LCD screen. The inverter board converts low voltage DC power (few volts) supplied by the motherboard to high voltage AC power (few hundred volts) needed for the backlight lamp.
When the inverter board works properly, the backlight lamp gets power and the LCD screen lights up. As a result, the image on the screen is bright.
HOW INVERTER CONNECTED TO LDC SCREEN
On the picture below you can see a typical laptop display assembly which includes the LCD screen, video cable and inverter board.
One side of the inverter board connects to the backlight lamp and another side to the video cable (LCD screen cable).
HOW INVERTER MOUNTED INSIDE LAPTOP DISPLAY PANEL
In most laptops the inverter board is mounted below the LCD screen as it shown on the picture below. You can get an access to the inverter board when you remove the screen bezel – a plastic frame around the LCD screen.
TYPICAL INVERTER FAILURE SYMPTOMS
Usually inverters fail in one of the following ways:
1. When you turn on the laptop, the screen lights up for a short period of time and then goes dark. You still can see an image but it is very dark, almost invisible and definitely not usable. When you restart the laptop, the screen lights up and then goes dark again. The laptop works fine with an external monitor.
2. Your laptop turns on but the screen remains dark all the time. You still can see a very dim image outline. The laptop works fine with an external monitor.
3. The laptop screen works fine for hours or even days, but sometimes it goes very dark as it mentioned above. When you restart the laptop, the screen works fine again.
Inverter failure symptoms are very similar to backlight lamp failure symptoms and in most cases you cannot tell which one is causing the problem until you replace either the inverter board or the backlight lamp. From my personal experience, inverter boards fail more often than backlight lamps. If you have to guess, replace the inverter first.
Laptop parts | Repair Man | 
December 26, 2008 3:14 pm
440 Responses to “Screen inverter board”
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Pages: « 18 17 [16] 15 14 13 12 11 10 9 8 … 1 » Show All
April 22nd, 2011 at 12:28 am
Hi
I have a hp paviliondv900, when it is switched on the monitor goes all blurry, if I push the screen back it changes colour,I then push down the bottom where the hinges are, the hinge on the left as you look at the screen seems to put it normal. Do you think the cables are loose on the inventer board? The screen doesn’t go black.
hope you can help
thanks
April 12th, 2011 at 11:19 am
Hi
Replaced my LCD screen on my Dell Inspiron 6000 wich had cracked.
Works fine, but the screen is very bright and cannot be controlled with the Fn+ up or down keys as normal. Screen resolution is the same.
Had to reshape the bezel and cut some plastic from the end of the inverter board to make it fit as the new cable to the backlight lamp was to short.
Anyone who knows what to do. Have I connected the cable upside down?
April 3rd, 2011 at 6:49 pm
sir
my laptop sony vaio model pcg fx-805 the screen is totaly black out but i can stil see the display i think its inverter board but i can’t find the exact inverter model that compatible with my laptop, i hope you can help me …
thank you
March 31st, 2011 at 2:06 am
Buenos días,
Llevo un rato leyendo en su página los comentarios de problemas y posibles soluciones que surgen con las pantallas de los portátiles, y he pensado que a quizas tenga la suerte de que me puedan aconsejar una solución al problema que tengo con un portátil Compaq DV5.El problema que me presenta es que al encender el portátil, la imagén aparece distorsionada y con un ligero movimiento o balanceo, casi no se reconoce la imagén.
Agradecería un consejo para su solución.
Gracias.
March 24th, 2011 at 12:59 pm
I would like to know how many volts power a backlight bulb. I have read 5v and seen 12v listed and over 1000v. so i have no idea. i have looked on line for replacements and they don’t list the Volts.
Thanks for your help!
March 21st, 2011 at 6:48 am
My screen symtoms are a little different. The laptop had Vista loaded, screen was fine, except that the dimmer didn’t work, it just did nothing when you dimmed, and after a few presses, it turned the light off. I came back on when you pressed brighten.
I have wiped Vista, and loaded XP Pro.
Now, the backlight goes off, when you run on battery, and comes back on, when you plug in the charger. Weird that a change of windows should affect it. Also, the cmos setup works ok on battery, but the backlight goes out when windows runs.
Plug in the charger, and all is ok, nice and bright.
Any ideas?
March 19th, 2011 at 7:52 pm
I need to remedy that. The screen is very bright, it’s like inverted photo negatives. Tried to turn the brightness down but that isn’t the problem.
March 19th, 2011 at 2:27 pm
My daughter’s Dell D400 laptop screen is showing images but they’re dark to the point of looking like photo negatives.
We replaced the inverter board and it stayed the same. We hooked it up to an external monitor and the screen was perfect.
Am I right or wrong by thinking of replacing the screen?
March 16th, 2011 at 8:29 pm
Hi,
my ACER Aspire 7720G Laptop shows “black” Screen after Power on – Win-OS is booting but Screen remains black.When connecting the Laptop to a LCD via external VGA connector then i can see the Boot-Screen but not able to read what is displayed because the ASCII-Characters are scattered and blinking.
After Boot-up the Windows Logon-Screen is clearly visible on the 2nd LCD connected via external VGA. What is the Problem? Do i have two deffective Parts i.e. VGA-Board + Inverter Board or something else?
Thank’s allot for help & Brgds
March 15th, 2011 at 2:11 am
Please if you wouldn’t mind help me say where my own problem lies. Similar problems with black screen, as a matter of fact, i am typing this with the back-light off, though i can slightly see what i am typing as the background of this page is white, otherwise i would barely see anything else.
precisely, my laptop is showing signs both for LCD lamp failure, and Inverter failure.
But here are my observations:
1) when i close and reopen the lid, it sometimes lightens up but only for some time.
2) If it tilt the lid backwards, more than about 110 degrees, it blacks out again
3) sometimes it blacks out by itself
4) When i slide my hand phone over the hinge (that is bottom of the screen, and on the power button’s panel), or let me say, over the inverter’s position, it lightens up again.
with this can i say it’s inverter failure? and how much will it take me to fix it. I use Hp Compaq, Presario C700.
Thanks.
March 8th, 2011 at 9:31 pm
Ok so one night my backlight stopped working so naturally i assume the inverter is to blame and order a replacement..
after replacing the inverter success the screen lights up again the problem now is after around 5 mins the inverter makes a high pitched sound and generates alot of heat followed by the screen loosing the light off the left side of the screen if left long enough before shutting down the backlight turns off completely…
i am inclined to believe the new inverter is faulty any ideas on the cause?
note: using the old inverter the back light dose NOT work at all.
March 2nd, 2011 at 8:19 pm
LIn,
Looks like you asked same question in another thread.
Here’s my suggestion:
Most likely it’s either bad inverter board or failed backlight lamp inside the screen.
There is no way to tell which one is bad without testing the laptop without another working inverter or backlight.
Both have similar failure symptoms – no light.
If you have to guess, try replacing the inverter board first. If it doesn’t help, try replacing the LCD screen (it’s very hard to replace just the backlight lamp).
February 26th, 2011 at 8:16 am
Stan Huang,
Display is fine, I mean I can connect an external display. But when I plug the LCD cable and the “ring” structure into the motherboard, it doesn’t Boot! I’m waiting for my new invertor but hey, do you have any suggestions of how to fix this problem?
This doesn’t sound like inverter related problem.
Take a look inside the video cable connector on the motherboard. Maybe you accidentally damaged pins inside the connector.
Are you sure the new cable is 100% compatible with the laptop? Could be wrong video cable.
—————
Hey,
I got a new motherboard. I also now have 3 cables…… they all fit fine. I don’t want to get a 4th one.. I believe at least one of them is working…
Do you know anything about the “ring” structure on gateway’s screen connector? I saw the downside of mobo and it’s just nothing.. is it maybe just something to keep the connect rigid? also on the ring thing, it used to have some metal but it has been scratched away.. because I remove/replaced so many times…
Also, I bought a new motherboard for another $60……Goodness this repair is taking toooooo much money input! And then I did see the BACKLIGHTS work before the “GATEWAY” Logo comes out… so another inverter is on its way….. I’ve also tried to use my ThinkPad to light up the screen when Gateway has displays and it worked flawlessly… So.. yeah. 3 cables…2 boards..2 inverter (probably both defective) and 3 displaying screens (1 broke)…
Anything else I should try? Thank you very much good sir!!!
I also used a newly fixed HP for some tests….
I put the HP’s inverter on Gateway… backlight dims…
I put the Gateway’s inverter on HP…. HP dims… and then the LCD cable place started extreme overheat! so I replaced them back to where it came from… and then HP works fine. so.. Very strange.
I also had a newly fixed HP Pavilion (video chip stuff) so I think I should share a little bit….
I discovered that.. I actually soldered with a hair dryer and a lot of aluminum foils and a soda can. I wrapped all the hp mobo around except a 1×1 centimeter square. and then I heated with hairdryer. I really wasn’t sure what temperature did I reach.. but I tried to flash it without melting that chip..
And then after it cooled down I used the ARCTIC SILVER 5 thermal stuff and used Penny Fix.. so then that family HP has been working fine since then… Before fix it was broke… “suffocation” fixed it to work but it works with sub-90 degrees celcius. And now it works with sub-50 degrees.. I hope the solder will work fine with this temp then……Part of the success is by watching your blog, so Thank You!
February 25th, 2011 at 10:55 am
Hi
One day out of the blue the screen on my laptop was black when I reopened the lid. I can see a faint picture in the background and sometimes if I press keys on the keyboard it will flash on quickly and go back off. Today sometimes when I open the lid there is a picture but it only stays on for around 10 seconds. Have you any ideas what might be the cause. Hope you can help. Regards
February 21st, 2011 at 10:46 pm
hydrod,
Sure it can.
The inverter board works as a power supply for the backlight lamp. If your “new” inverter is bad, the screen backlight will not work.
Wait for another inverter and try again.
February 19th, 2011 at 3:13 pm
Got the new backlight in today, hooked it up and it won’t turn on.
I played with the lid switch button till I’ve got a dent in my finger, that didn’t work! I even hooked up the old inverter and got nothing at all. With the (so called) new inverter I get a very dim screen, Can a bad inverter, even when it is suppose to be new not let the backlight turn on? I’ll order another inverter but if it don’t work, there is a very big river near here (Mississippi) that just might have another Tobisha for lunch.
February 11th, 2011 at 4:54 pm
Hydrod,
Did you check the lid close switch button? Maybe the switch suck inside the housing and the laptop “thinks” the display is closes even when it’s open.
Try tapping on the switch, maybe you can release it.
February 11th, 2011 at 4:07 pm
I’m working on a toshiba m35x-s3111, as with most m35x models I did a repair on the D/C plug (replaced) next what I thought was an inverter board problem has got me taking more asprin, the screen is very dim, external monitor will not work (tired 3)FN F5, I put a new inverter in and have the same problem. I unpluged the video cable from the motherboard and get nothing on the external monitor. OH! with no inverter board installed I still get the same very dim monitor. One other thing I just got the motherboard back from a repair shop in Miami, been working with them for years with no problems, I guess I just need a second opinion or a kick in the &*^(.
I’ve ordered a new backlight, can you think of anything I might have missed. ???
February 9th, 2011 at 12:11 pm
Stan Huang,
This doesn’t sound like inverter related problem.
Take a look inside the video cable connector on the motherboard. Maybe you accidentally damaged pins inside the connector.
Are you sure the new cable is 100% compatible with the laptop? Could be wrong video cable.
February 9th, 2011 at 12:07 pm
Chuck,
This problem is not related to the inverter board. That’s for sure.
This is LCD screen failure. The screen has to be replaced.
February 9th, 2011 at 11:46 am
Hi,
Great site. I have a Compaq 8510p. The screen will appear ok and then slowly deteriorate into black. If I tweak the top left corner of the screen the picture will come back. As soon as I let go the picture deteriorates again. I took it apart and checked all of the connections and everything is connected properly. I have read about the inverter but want to make sure it is an inverter problem before purchasing one. I found some videos on YouTube with other people having the same problem. Here is one of the videos. Not sure if it is OK to put a link in my post.
http://www.youtube.com/watch?v=uNMIx919mBw&feature=related
Please let me know what you think the problem is. Thank you very much.
February 5th, 2011 at 8:39 pm
Hi there,
I have a pretty tough issue. I have a Gateway W350I… T-6836u. It was originally working fine. And then, I poped the whole thing up just to clean up and improve heat dissipations and stuff. Then I put the whole thing back into shape… And I realize I broke the LCD Cable. And then I bought a LCD cable, but it still doesn’t work! I bought the cable from a reputable dealer, and I’m not sure if it’s the cable or the motherboard. Display is fine, I mean I can connect an external display. But when I plug the LCD cable and the “ring” structure into the motherboard, it doesn’t Boot! I’m waiting for my new invertor but hey, do you have any suggestions of how to fix this problem? Thank you so much so much!
Sincerely,
February 5th, 2011 at 2:33 pm
scottie,
The screen brightness didn’t work properly because the inverter board didn’t match the LCD screen. I’ve noticed same problem with many different Dell laptop.
Now, when I have to replace the screen, I make sure to buy one which has inverter attached. In this case it should work properly.
Maybe 17″ screens you are getting either bad or not compatible. If you want to install a compatible screen, search by the part number from the original 17″ screen. The 15″ screen still showing the image, it means the laptop operates properly.
I guess new 17″ screens have different native resolution from the original screen and because of that do not work properly. This is just a guess.
February 3rd, 2011 at 4:10 pm
Hi, I smashed my old screen for my dell vostro 1700 (17″) a long time ago, and replaced it with a 15.4 inch out of another dead laptop, worked fine, except the brightness, its dull and when you turn it up or down just is random to how bright it goes.
I have tried to change it for a 17inch screen I received, the back-light comes on, but still the problem of brightness everywhere but no picture. I blamed the screen, and ordered another one, same problem. but the 15inch still works fine.
I noticed on the inverter 2 points where it screwed to the original screen which seem to have a plate for to conduct electricity. Could this be why I’m getting no picture? or am I unlucky and have two dead screens?
January 28th, 2011 at 11:29 pm
danny,
It depends on how your screen is flickering.
Is it loosing image or backlight?
If the screen looses backlight but the image stays on the screen all the time, most likely it’s either bad inverter or failing backlight lamp inside the screen.
In this case try replacing the inverter board first. If it doesn’t help, replace the screen.