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Maybe the backlight failed. If you put a very bright lamp near the screen, you may be able to see faint differences in the various pixels that make up the Windows Desktop, Taskbar, etc (since you can see them on the external monitor too). I've seen this once on an iMac. It was really hard to tell, but with close examination it was noticeable.
I have an IQ770, the other day while on the computer it suddenly went black, as if the monitor had been turned off, I touched the screen and could hear the beep, but there was no visual display.
I restarted it and nothing, I touched the monitor and could still hear the beep...I plugged in an external monitor to see the desktop, I could move and click on items using the touch screen and noticed it still worked because I could see it on the external monitor, but the display on the IQ770 is totally gone.
I tried Function F5 and nothing works.
Has anyone else had their display totally go out and not work? How can I troubleshoot this, or fix it?
Apparently the monitor works if the touchscreen itself works, it just doesnt display, the video card must be working fine if I am able to use an external monitor.
Any help would be appreciated before I decide to throw this computer in the trash.
One note: I have had in the past about 5 bluescreen errors in the past 6 months, can't recall if any were related to video, but my computer has never had any problems, it was bought new, but is now out of warranty.
Please help.
Thanks, Jon
April 6, 2009 9:29 PM
April 6, 2009 9:47 PM
GeekTieGuy said: Maybe the backlight failed. If you put a very bright lamp near the screen, you may be able to see faint differences in the various pixels that make up the Windows Desktop, Taskbar, etc (since you can see them on the external monitor too). I've seen this once on an iMac. It was really hard to tell, but with close examination it was noticeable.Thanks for your response....but how do I fix it?
April 6, 2009 11:05 PM
That depends. On the iMac it was just a loose wire. Reconnecting it made the light come back. You may have to replace the backlight or the inverter for the backlight or both. It's hard to tell.
Are you able to see any LCD patterns with a bright light in front of the screen?
April 7, 2009 7:33 PM
I have **tried** several times to replace a LCD backlight and it is an exercise in futility. I would buy 3 or 4 lamps at a time because I knew that I was going to break one or two....and I have been servicing PC's for over 15 years.
Add on top of that the complexity of the touchsmarts innards and it would be a painful experience.
Anyway, to what GeekTieGuy said to do and shine a light on the screen while the computer is booted up. If the backlight failed, you will be able to see a dim image on teh screen. If the videosubsystem (videochip.card) failed, you will see nothing. There is also a chance that it could be the LCD's power inverter but they usually dont just quit, rather they present you with funky colored images first then gradually fade out.
My guess is that since you say you had several blue screen errors, there is a hardware or hardware dirver that is not functioning properly.
One last test...when you boot up the PC, do you see the HP splash screen before windows starts?
David
http://i99.photobucket.com/albums/l299/xz550rj/HPMagicGiveaway.jpg
Woohoo! I won my Touchsmart!
April 7, 2009 8:37 PM
DaveTN said: I have **tried** several times to replace a LCD backlight and it is an exercise in futility. I would buy 3 or 4 lamps at a time because I knew that I was going to break one or two....and I have been servicing PC's for over 15 years. Add on top of that the complexity of the touchsmarts innards and it would be a painful experience. Anyway, to what GeekTieGuy said to do and shine a light on the screen while the computer is booted up. If the backlight failed, you will be able to see a dim image on teh screen. If the videosubsystem (videochip.card) failed, you will see nothing. There is also a chance that it could be the LCD's power inverter but they usually dont just quit, rather they present you with funky colored images first then gradually fade out. My guess is that since you say you had several blue screen errors, there is a hardware or hardware dirver that is not functioning properly. One last test...when you boot up the PC, do you see the HP splash screen before windows starts? David
My screen is completely black, as if it were turned off completely.
When I made the external monitor the main display monitor, so when the computer turns on the boot screen is on the external display.
And I have to be real careful with "extending" video capabilities to the main monitor because it makes everything move over to the main monitor (the Taskbar and all icons).
I haven't shined a light on it, but when I turn the computer on I don't see the main display do anything, any flicker or anything at all...before when I hit Fn F5 I use to see a slight flicker, but not anymore.
I don' want to spend several hundred $ to fix this, I much rather backup all my info and sell the computer for parts or trash it.
Did you have the IQ770 with this problem and were able fix it?
Anyone else have any ideas? or Fixes?
Thanks in advance,
Jon
April 7, 2009 8:59 PM
OK, the fact that the external monitor works rules out most problems with the video card.
The fact that you can't see ANYTHING on the primary display makes me think that it is a badd connection between the display card and the screen.
An LCD is pretty much two systems; the video system which is the image that is generated on the LCD material and the lighting system which illuminates the screen. If the video fails the screen will still light up. If the light fails the image - although very dim - will still be displayed on the screen.
Makes me think that it may be a bad connection and I think I read about some others (two) here on the site that have had similar problems with the 700 series.
David
http://i99.photobucket.com/albums/l299/xz550rj/HPMagicGiveaway.jpg
Woohoo! I won my Touchsmart!
April 7, 2009 9:16 PM
updated: April 7, 2009 10:09 PM
DaveTN said: OK, the fact that the external monitor works rules out most problems with the video card. The fact that you can't see ANYTHING on the primary display makes me think that it is a badd connection between the display card and the screen. An LCD is pretty much two systems; the video system which is the image that is generated on the LCD material and the lighting system which illuminates the screen. If the video fails the screen will still light up. If the light fails the image - although very dim - will still be displayed on the screen. Makes me think that it may be a bad connection and I think I read about some others (two) here on the site that have had similar problems with the 700 series. DavidDavid,Even though I haven't shined a light on the screen, if the light fails the imge although dim should be seen even without the need to shine a light on the screen right? Mine you can't see absolutely anything.If you could send me links to others here on the site I would be very appreciative, I've searched but can't find anything.As far as the light issue you mention, is this something I can tamper with myself with some guidance? Let me know if you can help.Thanks,jon
April 9, 2009 12:32 AM
You need a very bright krypton or led flashlight to see the shadowy images on the screen. Depending on how the 770 is wired up, you may have to disconnect the external monitor in order to get a display signal sent out to the lcd screen of your 770. Try going back to just the 770 alone without the external monitor plugged in, and shine the light upward and try from several angles. If you still see nothing, try it in a VERY dark room, and cup your hand over the flashlight to shield your eyes from the glare. If still nothing, turn off the flashlight and check to see if you see any traces of light on the black background where the fluorescent light from the lcd is bleeding through, usually near the bottom and corners of the screen. I doubt that your blue screens are related, I'm betting money that your CCFL lamp is burned out, sometimes they start off by looking a little pink on startup, and it gets worse as time goes on, and sometimes they just burn out and leave you scratching.
DaveTN is right, I have changed many of these CCFL lamps, it's easy on a laptop, but this is the bottom of the stack of at least a hundred screws and pieces of Kapton tape and plastic clips, etc. I really wouldn't know what it would be worth to do the job, but it is at least 3 hours by a tech who has done it before, and the longer the tube, the higher the chances are of cracking or having bleedthrough after you are done. Plus, with plenty of the 770's out there on ebay and Craigs' List for sale for parts after only being in use for a year and a half, there's no guarantee that yours will live another 6 months after such a repair. The sting of the cost of the fix may still be with you long after the PC is sold for parts. If anyone out there has ever pulled the lcd on a 770, it would be nice to hear that there is a way to get it out from the front as is the case with a laptop. Let's hear from you if you have ever pulled the lcd from a 500 or 800 series TS as well. No reason for that yet since most all of us are under warranty, but there are a few who have voided theirs who might have such an experience.
Hope this helps,
Dave
April 9, 2009 12:40 AM
BTW,
If you see light bleeding through a blank display, you either have a loose, damaged, or disconnected signal data cable going to the back of the lcd screen, or the electronics are bad inside the panel. Also check the other end of the video cable that goes back to the motherboard LVDS connector. (LVDS1 or LVDS2 is the marking on the motherboard next to the onboard cable socket.) Good Luck!
Dave
April 9, 2009 1:10 AM
WaveRider said: You need a very bright krypton or led flashlight to see the shadowy images on the screen. Depending on how the 770 is wired up, you may have to disconnect the external monitor in order to get a display signal sent out to the lcd screen of your 770. Try going back to just the 770 alone without the external monitor plugged in, and shine the light upward and try from several angles. If you still see nothing, try it in a VERY dark room, and cup your hand over the flashlight to shield your eyes from the glare. If still nothing, turn off the flashlight and check to see if you see any traces of light on the black background where the fluorescent light from the lcd is bleeding through, usually near the bottom and corners of the screen. I doubt that your blue screens are related, I'm betting money that your CCFL lamp is burned out, sometimes they start off by looking a little pink on startup, and it gets worse as time goes on, and sometimes they just burn out and leave you scratching. DaveTN is right, I have changed many of these CCFL lamps, it's easy on a laptop, but this is the bottom of the stack of at least a hundred screws and pieces of Kapton tape and plastic clips, etc. I really wouldn't know what it would be worth to do the job, but it is at least 3 hours by a tech who has done it before, and the longer the tube, the higher the chances are of cracking or having bleedthrough after you are done. Plus, with plenty of the 770's out there on ebay and Craigs' List for sale for parts after only being in use for a year and a half, there's no guarantee that yours will live another 6 months after such a repair. The sting of the cost of the fix may still be with you long after the PC is sold for parts. If anyone out there has ever pulled the lcd on a 770, it would be nice to hear that there is a way to get it out from the front as is the case with a laptop. Let's hear from you if you have ever pulled the lcd from a 500 or 800 series TS as well. No reason for that yet since most all of us are under warranty, but there are a few who have voided theirs who might have such an experience. Hope this helps, Dave
Ok guys, so I turned off all my lights, got my off nice and dark, I looked through the vents on the back of the IQ770's monitor and could see light coming through the crevices of all the metal plates and whatnot....however with the room pitch black not even faint light was visible on the screen itself, so I got my cell phone and with just the light of my cell phone I could see all my desktop items.....So, with this discovery, what does it look like needs to be replaced or fixed? and how much would the part or repair for something like this run? is it something I can do with someone guiding me over the phone?
Thanks,
Jon
April 9, 2009 2:02 AM
First and easiest thing to try is the inverter. The lcd plugs in to it with a small 2 wire flat connector usually near the bottom right hand side of the screen. I'm a 526 owner, so I'm not sure how deep you have to disassemble to get to it, but certainly not as deep as pulling the screen to replace the CCFL lamp. Usually the inverter is a 3-4 inch by 1/2 inch circuit board with one small IC and maybe a couple of really small radial capacitor cans on it. It is a high voltage "starter" for the fluorescent tube used to backlight the lcd panel, so it has clear or translucent plastic insulator sheets covering it to reduce chances of shorting to nearby grounded metal parts. You might be lucky and find that you only have to reseat the connector and it jumps back to life. Since you didn't say anything about it getting a dim pink color on startup over the last few weeks, it could be a sudden failure of the inverter, but they usually last a lot longer than the lamp. Good Luck, I have to get to bed, hope you can get it back up and running.
Dave
April 9, 2009 8:06 AM
When I said shine the light on the screen, I was talking about the FRONT of the screen...the part the image is displayed on. If the backlight is burned out, there will still be an image. The flashlight illuminates part of the screen to see if there is still an image.
Waverider makes a good point too. Usually when a lamp goes bad you start seeing weird colors...usually pink hues...to your images. When an inverter goes bad, you will lose your image and then it may come back for a bit after rebooting.
Before you start taking things apart, try this. Since the inverter is usually mounted at the bottom of the screen, yse your finger to flick the case just below the screeen...NOT the screen itself, just the part of the case below the screen. If it is a loose connection, then it will likely cause it to make momentary contact and your display will come back on.
David
http://i99.photobucket.com/albums/l299/xz550rj/HPMagicGiveaway.jpg
Woohoo! I won my Touchsmart!
April 9, 2009 8:40 AM
Yeah, that's worth a try, and if it's a broken soder joint on one of the ends of the CCFL tube, try the "flick maneuver" on both sides of the bezel as the tube has solder joints at both ends of the bottom right and left sides of the lcd panel. They are usually inside rubber boots that hold them in place and insulate them from shorting at startup when voltages get really high, so if you are lucky, the screen may flicker on and then back off when you try this. It seems strange that you saw light from the vents in the back of the monitor, unless these were colored leds that signify power on condition on the motherboard.
Dave
April 9, 2009 8:43 AM
WaveRider said: .... It seems strange that you saw light from the vents in the back of the monitor, unless these were colored leds that signify power on condition on the motherboard. Dave
Thats what i was thinking...getting at. ;-)
David
http://i99.photobucket.com/albums/l299/xz550rj/HPMagicGiveaway.jpg
Woohoo! I won my Touchsmart!
April 9, 2009 8:43 AM
Dave, justg a thought. Is the screen LED backlit or CCFL?
David
http://i99.photobucket.com/albums/l299/xz550rj/HPMagicGiveaway.jpg
Woohoo! I won my Touchsmart!
April 9, 2009 9:25 AM
I'd bet that there are 2 CCFL's, although it might be only one REALLY long one, but fluorescent tubes are still the industry norm, and hardware-wise, I haven't seen any breakthrough technology on my 526 other than the touch capability. It's a PC built to laptop standards with a little aircraft tech thrown in to compensate for the weight of this thing. That's a good thing though, as in my opinion, it's a very well structurally built machine, just really not much thought went into making it an easily repaired unit.
Dave
April 9, 2009 6:18 PM
The light that was visible through the vents in the back wasn't much, not like my flat panel dell which on the back you can see tons of light...but there was some light nonetheless
DaveTN said:
"Before you start taking things apart, try this. Since the inverter is usually mounted at the bottom of the screen, yse your finger to flick the case just below the screeen...NOT the screen itself, just the part of the case below the screen. If it is a loose connection, then it will likely cause it to make momentary contact and your display will come back on."
I have actualy picked up he computer, moved it ievery angle, tapped it, raised and lowered the niter, tilted it, tapd every possibl corner and nothing.
I took the cover off the the actual computer portion, not the monitor, but I don't know what to look for.
Based on the image showing and no light coming through, what does it sound like might be broken, and how difficult or costly will it be to fix/replace?
April 9, 2009 6:41 PM
Since you can see a faint image on the screen you have two possibilities. 1. The inverter board is bad (most likely situation). The inverter board is like a "ballast" for flourescent light tubes. With a bit of skill and knowhow, it can be replaced. It will require quite a bit of "surgery" on your part to get to it though. I'll try to post a picture of what an inverter looks like. It won't be a picture of what the touchsmarts inverter looks exactly like though. Inverters usually cost anywhere from 30.00 to over 100.00 and you must purchase EXACTLY the one your computer requires or you risk other damage.
2. The CCFL or "light tube" is burned out. These usually burn out slowly and you will notice a shift towards pink/purple on your screen image before they fully die. Sometimes it will also take some time for your screen to "brighten up". The light tube is very difficult to replace and very difficult to get at. You literally have to disassemble the LCD to get at it. and thats the easy part. They usually break when you put things back together. A CCFL is about as thich as packing twine (3mm) and very rigid but fragile. If it cracks, it's done. I have purchased light tubes for anywhere from 9.00 up to 50.00.
Labor costs: Do it yourself - the cost of the parts. Have a reputable repair shop do the job...about 150.00 to 300.00 in labor plus parts.
Hope that sheds a little "light" on the subject for you.
David
http://i99.photobucket.com/albums/l299/xz550rj/HPMagicGiveaway.jpg
Woohoo! I won my Touchsmart!
April 9, 2009 6:51 PM
Again, it's an inverter or a lamp, or both. An LCD screen in new condition for one of these 770's is probably 600+ bucks, I don't know if there are any on ebay for sale, but they'd probably be $250 or so, the inverter is probably $25 or less used, and $125 new, I'm guessing here, the parts are not flooding the repair market yet, I assume since HP changed the TS so dramatically after only 1-1/2 years of 700 series production, there are a lot of them in basements, attics, etc. waiting for repair costs to go down if at all, they may well be destined for the trash due to lack of parts. I would tend to believe that if one were to disassemble one of these machines, that most of the major components were available as generic replacement parts, maybe the same lcd and inverter are used in other manufacturers' products. Otherwise, the TS would have been just way too expensive for the consumers they were directed at and would only reside in secretive US Govt. facilities...
It would be nice to have access to the repair manuals, spec sheets, parts lists, and drawings, but that info is for ASC personnel only, so until someone gets a copy of it all on a DVD and sells it on ebay, we will have to wing it.
Dave
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