Second GTX 770 not recognized properly

[Jrzimm612]

SLI PROBLEM
I think my motherboard PCIe slot is bad. Please help.

I just upgraded from two 8800gt in sli to two evga gtx 770's in sli. The second card cannot be recognized by the nvidia control panel. Device manager gives it a exclamation point saying there was an error (43?) and the device was deactivated because it reported an error. Here is what I have done...

Uninstalled drivers with driver cleaner in safe mode and reinstalled.
New installation of win 8.1 64
New installation of win 7 64
Again back to win 8.1 64 after drive formatting
Updated bios
Deactivated integrated gpu in windows
Selected PCI e version manually in bios
PCI e confirmed as primary display in bios
Reinstalled cards multiple times and one at a time. Both cards work.
Confirmed in gpuz that both cards are functioning and getting voltage


My 8800gt sli setup was flawless... What has changed!?

My rig:
Intel 2500k @ 4.4
Gskill ram 16gb (4 sticks)
Asrock z77 extreme 6 mother board
Thermaltake 850 watt sli psu
2 x evga gtx 770 SC's
Windows 8.1 pro 64
Latest certified nvidia drivers
Latest mb drivers from asrock

Thanks for any help!

 

[Shaun o]

Possible causes as to why SLI is not working

1. Two ribbon bridges need to be connected between the two cards, one will not yield Sli mode.

2. The cards may have to be placed each in the right slots provided by the mobo.

3. The clock rates of the cards may differ slightly from each, and must be set running at the same frequency each for memory speed, gpu and shadier speeds. Then Sli mode enabled in Nvidia driver app.


4. Check that the eight pin power phase to motherboard is connected right, and the extra Pci-e 12v supplys from the Psu to the two 770 cards.