Graphics card display problems

alu7616

Honorable
Jan 8, 2014
20
0
10,510
So i recently made a cheap pc for a friend .
We plugged the graphics card in and it seems to display white horizontal lines across the screen.
It doesn't have any built in graphics on the motherboard so i tested it with my spare graphics card.
My old 9400gts works fine in his PC.
The card (7750) has the same issue in my PC.
The card is a Sapphire 7750 1GB.
We have tried contacting the seller but haven't got a reply in 2 months now with multiple emails so were wondering if we have a expensive paperweight here or if there is some sort of possible fix.
 

alu7616

Honorable
Jan 8, 2014
20
0
10,510


having never worked i don't think its a problem with the solder or anything like that, if worst comes to worst im sure i can try it as a last resort.