Dell Alienware 17R5 - Can not boot - 3/2/1 beep code and 2/7 led code

Описание

(Beep code start at 00:17)
My Dell Alienware 17R5 (Service tag: 4VHWTP2) is diagnosed with faulty GPU. I am looking for a solution. My idea is try booting laptop without GPU and using Alienware Graphic Amplifier with external VGA card.

Update 12JUN2021: As far as I know, the problem is caused by either broken LCD/LCD cable or VGA chip. I’ve bought a new cable that connect mainboard with LCD (part number: 0WXKDC). Unfortunately, after installing the new cable, the error was still occurred. A new LCD panel also did not help.
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Update 02 MAY 2022: Connecting HDMI to external Monitor does not help. I decided to get a new mainboard for my laptop. In summary, I think gaming laptop mainboard is sensitive to temperature, humidity and dust. Sadly, these stuff are popular in my country - a tropical one.

My advice is to take care of your gaming laptop, especially keep it cool, clean and avoid power disruption (which can cause short-circuit on mainboard). Otherwise, you gaming laptop could die as mine.
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Update 22 JULY 2022: My local shop can not find any other mainboard for replacement. I was tired of waiting, so I gave up, sold away the dead laptop and built a new PC.