XPS M1710 Black Screen, works with external monitor. 3 LED's one still others blinking.

Hi, all!

Recently my XPS's 7900 GS began to die, so I bought another card off ebay. Unfortunately, the XPS is refusing to show anything other than a black screen unless I disconnect the LCD cable, and connect the XPS to an external monitor where it works perfectly. In other words, it does not post if the LCD cable is connected. It does this exact problem with the 7900 GS also which has a small amount of life left in it.

Any help would be much appreciated

 

It is possible for failing GPUs to only work on an external display, and not on the internal display. Was the replacement car you bought guaranteed working? You might also have a failing display, though.

 

This is the card I bought Dell E1705 M90 9400 M1710 NVIDIA Go 7950T GTX 512MB Video Card XJFPC | eBay

Seller says that it's "New" and checking his feedback it seems that several others have bought it and haven't had a problem. I've also bought I new display cable to confirm that it is the display. It was working perfectly until a few days ago.

 

It is possible that it may have a issues without the seller knowing (those who do retro builds know how things can go) so I would contact the seller to send another and if the same results it is likely a damaged cable/connector.

 

The seller has offered me a replacement. I just need to post it back to them, and if this "new" card gets the same problem, I'll be fully convinced that it is the display/cable.

 

UPDATE: Got a new card and it has exactly the same problem. External monitor = Boot straight into windows. Display connected = no boot.

Swapped out the display cable with a new one and the same problem persists. Is the display gone? or is it a motherboard fault? The display lights up and everything, but is black.