Hi,
8 beep codes indicate “LCD failure”. In your case as it is apparent that the video is distorted on external monitor and also you hear the indicator-beep-codes, we need to troubleshoot for both LCD problems and graphics card. Please follow the steps below and see if this fixes the problem:
1. Sometime the LCD cable not connected correctly can cause beeps. Take help of a local technician or yourself try to reseat the LCD Cable.
2. You can find steps on how to reseat the LCD cable on page number 20 of the Service Manual. You can download the Service Manual from the below mentioned link:
http://dell.to/12kCHjY
3. Perform the step only if you are comfortable doing it else take a technician’s help.
4. Before starting the troubleshooting mentioned in step 1, please go through the “Before You Begin” section of the Service Manual.
Note: In case of expired warranty scenario, I would be able to provide limited support, which will not cover part replacement, software support and onsite technician.
Do reply with results for further course of action.
Thanks & Regards
Zohaib R
#iworkfordell
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