Graphic Card gives no display but shows up in device manager on inbuilt display (Really need help)

[wellwisher993]

Hi, this is my first post here

I had a fine working system. somehow one day it was short circuited and that burned my graphic card, modem, motherboard and processor.
So I bought a cheap used motherboard and a new processor. Found some issue in MoBo so got it repaired Gigabyte Service Center. Got replacement for graphic card as well. Installed everything in new system. Now what happens is, everything seems to work fine. But GPU is not giving any output. I can run system on internal GPU.

Here are the things I tried:
Tried fresh installation of windows as well as GPU driver. No Help.
Tried the Display on different system, display is fine.
Tried with different display as well but no help.
Also tried changing RAM.
Tried with a different HDMI cable. Same results.
Tried Installing external GPU and then using internal GPU to boot. I can boot in windows and see the external GPU in device manager. Everything seems to be fine.

Can someone help me with this issue. Its been months I am trying to save this PC.

Thanks

Below are my system specs:

Old Specs:
Asus M5A78LM-LE
AMD Phenom II x6 1050T
Kingston 8GB DDR3 1333Mhz
Asus Strix GTX1060 6GB
Seasonic S12II 620w PSU

New Specs:
Gigabyte GA-78LMT-USB3
AMD FX-4300
Kingston 8GB DDR3 1333Mhz
Asus Strix GTX1060 6GB
Seasonic S12II 620w PSU

 

[WyomingKnott]

Have you tested the card in another machine, or tested another card in your machine, to isolate the issue?

 

[Obakasama]

May as well ask the silly question: have you plugged the display connector to the graphics card?

 

[Ferman312]

May as well ask the silly question: have you plugged the display connector to the graphics card?

He said that when he plugs in the graphics card is has no display.