Flickering monitor, but laptop functions fine

I'm going to take an educated guess here, because it sounds like the monitor's interface controller is bad. I forgot the name of the thing, but it's a small circuit board that's normally located at the bottom of the panel frame, between the flat ribbon cables and the round hinge cables.


"Inverter Board"

My sylvania cl772B turns on and shuts right off. what can I do?

The flickering could be a sign that your lcd screen is going bad and needs to be replaced. It could also be the video card inside the computer. Isolate the problem by connecting another monitor to the laptop. Borrow a monitor from a neighbor, friend, relative or co-worker and connect it to the laptop. If the Borrowed monitor displays ok without flickering, then your video card inside the computer is good, but your lcd screen is bad. If the Borrowed monitor flickers like your lcd screen did, then your video card inside the computer is bad.

Plug in an external monitor and see if the display shows up on it. It can be any kind of monitor even the old big fat crt monitors as long as it has a vga cable to connect to your computer's vga port. If so that proves your video card is ok. The video will show on most systems when you reboot without you having to do anything. Some systems will require you to hit the FN (Function key) + F1 thru F12. Hold down the FN key then hit the correct key for displaying on the monitor (F1 thru F12). The correct key will normally have CRT/LCD on it or it will have the icon of a display.

Try tapping the back of the lcd screen's lid to see if the flickering stops, increases or decreases. It might be that the lcd cable located at the top on the back of the lcd screen is loose.Isolate the problem by connecting another monitor to the computer. You'll have to take the lcd apart to get to the video cable on the back of it.

When you say flashes, is it like portion of the screen flickers?

If the flickering/flashes starts in Dell screen just right after turning on the laptop, when you see the Windows logo or just right after you log in to windows?

Try connecting your laptop to an external monitor then toggle display. To toggle the display to external monitor you can try holding down keys such as the function keys.

If the problem persist from the external monitor it means the problem is the motherboard or the video/graphics card.

If no problem from the external monitor this means laptop LCD and LCD cable needs to be replaced.

Hope this helps.

please check the monitor or LCD that you have. because the computer will not flicker if there is a problem on the display. isolate it. use other monitor or LCD then check if it flickers again.

You get white screen glow when the T-CON board on the LCD panel does not receive the +5dvc feeding it or it has blown fuse on the T-CON board, see picture of the T-CON board and the fuse here:
http://s807.photobucket.com/albums/yy352/budm/LCD%20panel/
Look at the logic board to see if the ribbon cable may have come off the LCD panel or the logic board, also look to see if you can see any bad caps (leaking/bulging top).
http://s807.photobucket.com/home/budm/allalbums
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.badcaps.net

You may have a defective CCFL backlight, it may have the following symptom: Screen flashes on and off or displays reddish pink hue. Picture stays on in red and slowly be come normal. Picture flickering with dim display or appear black. Picture flickers on and off. All these symptoms indicate that the LCD backlight lamp (CCFL Lamp) has reached the end of the life and all you need to do is replace the CCFL lamp.
To determine if the video card or the LCD is faulty, connect an external monitor to your laptop and power the monitor up first then the laptop, if you see the normal Windows images then the video card and laptop is OK and the problem is definitely the backlight. Dim image and/or dark display on the laptop's LCD screen indicates a faulty LCD backlight. It could be a faulty inverter that supplies high voltage to the CCFL lamp or it is the CCLF lamp is nearly burnt out, usually the CCFL lamp fails before the inverter.
The inverter can be replaced easily but the CCLF lamp is more time consuming and requires soldering skills.
Check out LCD Parts for service, parts, and DIY info Use this link to their WEB site: -
www.ladparts.net

If you've replaced the LCD Panel already, then chances are good, the failing part may be the FLR inverter. It's a thin little chip about 3 or 4 inches in length that bridges the connection between the LCD and the motherboard. It's location varies from computer to computer though, so you may have to check with manufacturer documentation. They're not too terribly expensive to replace though, much cheaper than the LCD panel, anyways.

the monitor green light comes on but the monitor itself does not come on. Sylvania LCD CL722b-Model 780

Bad LCD. That line is terminal - on the back of the pannel there is a circut board that can fail a line of pixels where they will no longer switch between colors. It's a common LCD problem, but for all intents and purposes its fatal.