Inspiron 3521, Flickering vertical & horizontal lines, purchased Jan. 2014

If you haven't done so yet I suggest updating the video drivers. 

For Windows 7

Intel HD 

AMD 7670m

AMD 8730M

For Windows 10

Intel HD

AMD Radeon

I hope that this helps.  If you continue to have problems please reply with the version of Windows that you are using. 

Thanks

TB

Definitely try updating all your drivers first. Ultimately you might have to send it back. I did that with mine and it turns out a cable connecting the screen with the comp was faulty. Good luck!

Yup, I did update the drivers.

I just made things worse.  I followed a couple youtube videos and took off the plastic screen frame and exposed the LCD screen.  I loosened the screws as indicated and twisted the screen gently to see if the lines got better.  It all got worse.  And then it went black.

I put it all back together and when I re-booted, it beeps at me 8 times in a row.  After another search and releasing any static energy, it still beeps.  I believe it beeps because the display is not working.

I now think my main problem is the backlight inverter and maybe it has been all along.  I do remember one section was really hot to touch (unsure if it was supposed to be that hot).

I'm going to call Dell and see how much that part might cost for replacement.  I see a refurbished one on Amazon is like $20.

Any other advice?  

How much did that cost?  

You sound like you are on the right track, one thing that I suggest before purchasing another LCD is to connect an external monitor to the system and see if you get a image then.   That will verify if the GPU on the system is still functional and that the problem lies with the LCD.   

If you get no image at all on either the integrated LCD nor the external monitor then you are likely looking at a system board / GPU problem. 

Please let me know what you find out.

TB

I hooked up my computer to my TV and to my surprise, I could see my computer screen on my TV.

Guess it was the LCD screen after all!

I checked for this part on dell.com, but wasn't able to get it as a replacement part, but I did find one on amazon for $35.  

Thank you for the advice.  Anything else I should know before I purchase a replacement?

-k;)

I am glad to read that this isn't a problem with the system board. If you are comfortable doing the work yourself here is the operators manual where you can find instructions on replacing the LCD. If you can't find a suitable LCD accept my friend request and I may be able to suggest a part number. 

TB

I was going to order this:  https://www.amazon.com/gp/product/B00FN9AILY/ref=ox_sc_mini_detail?ie=UTF8&psc=1&smid=A3KYUJ2NI65EO

www.amazon.com/.../ref=ox_sc_mini_detail

Ok, I accepted your friend request.