Thanks for the tips guys. I tried with different drivers, and with the 7900 still no joy...
The risers are fine as they work with other cards, but id be mad to put in the riser the wrong way...
![Shocked](https://bitcointalk.org/Smileys/default/shocked.gif)
The 2 other cards were not posting at all, so i rmad all 3 of them. It turned out that they were actually from a bad batch and they had more ppl return cards from RMA with the serial number ending in uneven number in this batch. All 3 dead ones i had, the serial numbers were ending in 3, 5 and 7.
Anyways, new ones on the way, so really hope this story will not repeat
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)