Defect: Screen remains totally black, but Windows starts

Hi EP121 community,

I have had my EP121 since April (ordered from amazon.com USA), living in The Netherlands.

Besides a minor problem (pen digitizer not sensitive on the right size, for about 4 vertical pixel rows), my unit has worked flawlessly during the 3 months that I have owned it.

This morning, when booting up from hibernated state, the screen remained totally black.
Here's what I do see / hear:

• The adapter is plugged in and the LED on the left side is green. So the battery is charged and the power is plugged in.
• After the first confusion, I managed to forcefully turn off the EP121 and after turning back on (power slide on the top), Windows seems to boot up.
• After booting, I can hear the Windows start up tune. So the CPU, the motherboard and SSD drive seem to be working OK.
• When I enter my password with the bluetooth keyboard (tricky, I know, used backspace a lot), I can also hear the "successful logon" tune.
• When off, the LED at the top of the unit is off and the fan is silent.
• When on (before and after Windows tune etc.), the LED at the top is white (normal when on, if I remember correctly) and the fan runs (silently, as normal)
• I have used the reset pinhole (between the 2 USB ports), which turned off the unit. After turning back on, there was no change in behaviour.
• It is important to note that the screen remains totally black. So no blinking cursor during initial boot or anything. This is different from these 2 other cases that I found on the forum:
  http://forum.tabletpcreview.com/ep121-slate/38700-so-my-ep121-seems-have-died.html
  http://forum.tabletpcreview.com/ep121-slate/41376-my-ep121-just-died-any-suggestions.html
• Invalid observation: It is relevant to note that the sceen is totally black. So even when held under bright sunlight, there is nothing to see. I mention this, because one of my previous Dell notebooks had a problem with the inverter or CCFL light where a dim, unlit image could still be seen under bright light from the top.
• Corrected observation:The above point was my first impression, but when I pressed the Windows-button (on the BT-keyboard ofcourse), a very dim change on the left-part of the screen was visible. It is the the Start-menu that appeared. So the screen still works, but there is a problem with the backlight. The AFFS+-screen with broken backlight is much darker, more black than TN screens with similar defects.

My diagnosis from the above is that there is a hardware failure related to the backlight of the screen. Without opening up the unit (which I have no intention of doing), there is probably not much else to try.

Here's what I still plan to do:

• I have a mini-HDMI to HDMI cable, but no monitor with HDMI or DVI in the house at the moment. I have opportunities on Sunday and Monday to attach to a HDMI screen, so I shall see what happens.
• If the unit does not automagically return to normal, I shall contact Asus Netherlands first, to see what they can do (the EP121 is still not available in my country). I prefer not to have have my unit sent back to the USA, with the shipping cost, possible customs hassle and extra time involved.

So this is my experience and plan so far.

Does anybody else have any pointers or tips?

• Do you have suggestions of other things that I can try?
• Do you (like me) live in a country where Asus does not (yet) sell the EP121 and did you have a warranty issue? How was your experience with contacting your local Asus support?

 

For the first readers of this post: I have updated the above sections of the initial post. This is definitely a backlight problem.

 

Bum, sorry to hear that.
The only thing that I can suggest, is trying to enter the control panel backlight settings, turn the backlight down and then back up again.
Doubt it will work, as it soulnds like a true hardware failure. (unless you want to open up the slate).

The reason I suggest it is that I did have another windows device, which occasionally would go almost black. Even on a reboot, when it was usually a bright screen, it was black. It seemed that somehow the backlight setting got set to above MAX, which made it come up as below 0.

 

Thanks, I shall try that when I get control with by attaching an external screen.

I have already tried to get into the screen brightness settings, but it is almost impossible, because with the extremely dim screen I'm almost blind, so to say.

My standard brightness setting (when using the EP121 indoors) is less than 10%, which is quite extreme. So your suggestion definitely makes sense.

 

can you boot from a USB and see?

If problem persist...either lamp connector is loose or hardware failure..

 

Try ruling out that for some reason the video output is not redirected to the HDMI. If you have the cable, is worth the shot connecting it to an external monitor/TV and try to reset the tablet as the main screen.

 

Thanks everyone!

I was at a friend's today, who is an artist. One of the main reasons for the visit was to show her my EP121, who also has her attention since I told her about it in February. So it was a big bummer indeed to have this failure happen exactly this weekend.

While I was there, I could attach the tablet to her flatscreen TV over HDMI, though (in clone mode), so I could give show her Artrage and the pressure sensitivity of the Wacom digitizer.

While I had the EP121 attached to the TV, I could change the backlight settings, but this did not change the effect. Still an extreme dark screen, with only very dim visibility of light gray areas such as the start menu and dialog boxes.

I tried booting with CD-rom from my Hiren Boot CD, but I get also "no screen" during the boot process. I say "no screen", but what I mean is that I cannot distinguish anything on the screen well enough without the backlight on.

I am going to try again when I have my access to my own HDMI-enabled monitor later this week, but I don't think that it is e.g. a Windows driver issue.

That is a good suggestion for anyone with a similar problem, but it is not the case here.

Besides that I can hear that Windows boots, I can also see that the screen is on (although I missed it initally, because it is extremely dim).

Preliminary conclusion / what's next
The situation seems to be a hardware problem (backlight off, broken or disconnected). My next step will be to contact Asus support in The Netherlands. I shall keep you updated on how this goes.

 

yes..hardware problem..should send it in to be fixed.

 

I know what you are going through... i'm supposed to receive my unit back from RMA this week (SDCARD slot not working problem).

So i wish you good luck, and keep us posted on how that goes!

 

Hi

Underclock, the exact symptoms your describing of the extremely dim (almost like if the screen is off) screen your having happened to me once, but in this case it was my fault, so unfortunately you and the above posters might be right and could be a hardware problem, but I guess it won´t hurt if you try what worked for me.

I´ll try to explain and make the story short.

In my case it happened when I updated the display drivers (Intel hd graphics), and prior to installing the new ones, I went to the 1-Control Panel 2-Programs and Features, and from here I unistalled the Intel HD Graphics Driver. As soon as the driver was uninstalled the screen turned in what your describing. I uninstalled the old drivers because this is what I do when I update the Nvidia card of my desktop, prior to installing new ones, so I thought the same would work on the ep121 (wrong!! ).

As the screen was so extremely dim (my first thought as you tell in your first message is that is was totally black) I had to use a powerfull flexo lamp directly pointing to the screen and play with different angles to see something and manage to install the new drivers that I had downloaded in a pen drive. This worked for me.

I know it´s a very different situation but the symptoms are the same, so althought the chances that it will work for you, I guess (hope I´m wrong) are unfortunately small (somehow your display drivers got corrupt?), as I said before it won´t hurt to give it a try and reinstall the Intel hd graphic driver.

Good luck!

Kind Regards