I just sold my Sapphire 4870x2 out, when the buyer got it he complaint the card is faulty, with lines at screen. I think this is not driver issue because that happen before loading OS too (even in POST). Please help. The card was working perfectly when i pulled it out and delivered. Could it be power supply problem? The buyer is using 620W PS, what brand i donno. The buyer said he has tried on different Motherboard, CPU & monitor, still the same. The buyer does not have 8pin connector from his 620W PS and use the given 2x4->8 pin converter (as in photo).