Jump to content


 


Register a free account to unlock additional features at BleepingComputer.com
Welcome to BleepingComputer, a free community where people like yourself come together to discuss and learn how to use their computers. Using the site is easy and fun. As a guest, you can browse and view the various discussions in the forums, but can not create a new topic or reply to an existing one unless you are logged in. Other benefits of registering an account are subscribing to topics and forums, creating a blog, and having no ads shown anywhere on the site.


Click here to Register a free account now! or read our Welcome Guide to learn how to use this site.

Photo

replaced laptop screen, it doesnt work in bios but works in OS(internal screen)


  • Please log in to reply
9 replies to this topic

#1 nickpaokgr

nickpaokgr

  • Members
  • 6 posts
  • OFFLINE
  •  
  • Local time:10:37 PM

Posted 15 November 2017 - 11:45 AM

Hi I today replaced a broken screen on toshiba satellite c50-b-14h and the most strange thing that i have ever seen happened. So here is goes. Everything is connected correctly BUT when i power on the laptop i dont see post screen, or toshiba splash screen or uefi but if  i wait a little the os loads up and everything works fine. The screen works in OS but not in bios. Its like the bios i missing drivers for the screen or they cant co-operate to set up resolution. But windows does open correctly. i ve tried to change bios display options via system setup (toshiba tool) , if i set to vga, i can see the bios in the external screen . If i choose auto or system lcd only i see nothing. Is there any work-around to fix it ? . 
p.s. it's not fast start up issue
thx in advance


BC AdBot (Login to Remove)

 


#2 nickpaokgr

nickpaokgr
  • Topic Starter

  • Members
  • 6 posts
  • OFFLINE
  •  
  • Local time:10:37 PM

Posted 15 November 2017 - 01:56 PM

bump 
ps 2  my screen works in csm mode but not in uefi


#3 mightywiz

mightywiz

  • Members
  • 841 posts
  • ONLINE
  •  
  • Gender:Male
  • Local time:01:37 PM

Posted 15 November 2017 - 02:25 PM

pretty simple if you verified all cables are seated correctly then you probably got a defective screen that only works in certain resolutions.

each screen has it's own controller built on it and that's what could be bad.   send it back defective, and get an exchange.

 

tell them your issue is it won't work at lower 640 x 480 resolution for bios screen.

 

you can verify this by changing the resolution in your display settings try lower resolutions and if screen goes blank just wait and it will pop back in about 15 seconds.  all screens should be able to do 640 x 480.



#4 nickpaokgr

nickpaokgr
  • Topic Starter

  • Members
  • 6 posts
  • OFFLINE
  •  
  • Local time:10:37 PM

Posted 15 November 2017 - 03:22 PM

pretty simple if you verified all cables are seated correctly then you probably got a defective screen that only works in certain resolutions.

each screen has it's own controller built on it and that's what could be bad.   send it back defective, and get an exchange.

 

tell them your issue is it won't work at lower 640 x 480 resolution for bios screen.

 

you can verify this by changing the resolution in your display settings try lower resolutions and if screen goes blank just wait and it will pop back in about 15 seconds.  all screens should be able to do 640 x 480.

yes but in csm mode the screen works in bios (that's graphical btw and probably has bigger resolution than 640x480) so it's probably not the resolution, in uefi i dont even have backlight (if it was resolution related,if it was resolution related at least i would have backlight , right?)  Further more i can not set resolution 640x480 on the screen , the least i can do is 800x600 and it works perfectly there.



#5 mightywiz

mightywiz

  • Members
  • 841 posts
  • ONLINE
  •  
  • Gender:Male
  • Local time:01:37 PM

Posted 16 November 2017 - 05:55 PM

if it's got a signal problem and not communicating the screen size detection then it may not turn on the backlight.

 

as a tech that's replaced lots of screens, if you got a replacement screen that's not working correctly in all modes it's defective.  call the company and get an R.M.A. number and return it!



#6 nickpaokgr

nickpaokgr
  • Topic Starter

  • Members
  • 6 posts
  • OFFLINE
  •  
  • Local time:10:37 PM

Posted 17 November 2017 - 05:08 PM

if it's got a signal problem and not communicating the screen size detection then it may not turn on the backlight.

 

as a tech that's replaced lots of screens, if you got a replacement screen that's not working correctly in all modes it's defective.  call the company and get an R.M.A. number and return it!

But how it's possible to work well when i have csm settings on, because of that i think it's my uefi's problem (something with communication to the device) rather than lcd problem. 

thanks again for your help



#7 mightywiz

mightywiz

  • Members
  • 841 posts
  • ONLINE
  •  
  • Gender:Male
  • Local time:01:37 PM

Posted 17 November 2017 - 05:57 PM

because your CSM is dictating what resolution to use, it can emulate bios mode and still be at a different resolution.  I don't know about your bios but a lot of UEFI modes are graphical now and at a higher resolution then the legacy bios mode.   

 

anyways if the original screen worked correctly and the replacement doesn't then it's going to be a bad replacement.  quit over thinking it!



#8 nickpaokgr

nickpaokgr
  • Topic Starter

  • Members
  • 6 posts
  • OFFLINE
  •  
  • Local time:10:37 PM

Posted 19 November 2017 - 11:38 AM

i m overthinking it cause i have some other little problems too , like camera not working ( a while now , it has nothing to do with the screen) and I m wondering if my uefi is corrupted. I have to be 100% sure it's somehow corrupted because the bios is AMI's bios but it's custom edited by toshiba providing me very few options to change etc. and it's 50-50% that it will work if i modify it. Also i have the latest version of the bios and i cant reflash the same one, so the only option is to edit it ( or maybe just change the version so it can be reflashed) if it's bios related. 


Edited by nickpaokgr, 19 November 2017 - 12:23 PM.


#9 mightywiz

mightywiz

  • Members
  • 841 posts
  • ONLINE
  •  
  • Gender:Male
  • Local time:01:37 PM

Posted 20 November 2017 - 10:22 AM

does the camera try to turn on and you just get a black screen?  they move out of place easily when you disassemble the screens.  I'd also double check the wire going to the camera make sure it's in snug.



#10 nickpaokgr

nickpaokgr
  • Topic Starter

  • Members
  • 6 posts
  • OFFLINE
  •  
  • Local time:10:37 PM

Posted 20 November 2017 - 05:21 PM

does the camera try to turn on and you just get a black screen?  they move out of place easily when you disassemble the screens.  I'd also double check the wire going to the camera make sure it's in snug.

no, i told you , that camera stoppped working long time ago. About a year and a half. That's why i m curious if its uefi bug/corruption. 






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users