Was looking through the forms and seen a few discussions on this topic, but haven't seen any one saying it affected there speeds. Yesterday I connected two 6970's, in a x16 both directly into the board, and a 290, in a x1 slot, with a x1 to x16 riser cable and the 290 is running slower than either 6970 using md5 and wpa2. Is this normal or do I need to reconfigure my cards for maximum bandwidth?
The riser cable is a ribbon non-powered.
A PCIe riser on paper won't affect the speed of the card in regards to password cracking. You aren't even filling up the 1x with that much data. In reality, however, the quality of the riser will greatly affect the data transmitted over it. And a majority of what they sell for coin mining is crap. If you got one of those, you are probably in for a world of hurt.
These days, it's generally recommended not to use risers, although you can if they are of sufficient quality.
(It may also be worth mentioning, shorter cables are better).
can you run the oclhashcat benchmark mode and see the same performance degradation?
Thanks figure it out lol... the 290 was in kh/s and the 6970 was in h/s uggg lol