Question if i own a gtx 660ti and gtx 780 work with both

[relox]

Hi to all thanks if any have a feedback for this, i have got a gtx 780 but i want to use the gtx 660 ti too to use it for windows and the gtx 780 for rendering, now the problem i have a mother board gigabyte z77 ud5h, i plug-in both cards but in windows it detects the gtx 780 only that is pluged in and the gtx 660 ti its says in windows that the card hasnt resources to make the video device work so i want to know if im correct that the pcie expres says that runs at 8X the second pcie slot and the first runs at 16X, so the mother board need to have two pcie slots that runs at X16? not one?, im consider changing to an asus sabertooth z77 does it will resolve the issue i have read sabertooth z77 has two 16X pice slots.

thanks i appreciate any suggestion to make the desicion upgrading to asus sabertooth.

my specs are

i7 3770k
gigabyte z77 ud5h wifi
gtx 660 ti
gtx 780
cool master psu 1000w
16 gb ram.

[mib2berlin]

Hi, your board switch to 2x8 if you put two cards in but it is more than enough to work with Octane.
Place the 660Ti in the first slot and connect the display to it.
Search for PCIe first card or similar.
You can setup the "render" card in Octane independent from hardware position or BIOS settings.
Did the 660Ti work for display without the 780?

Cheers, mib

[relox]

Thanks mib2berlin, both cards are working fine if i only conect one to the first pcie slot but when i attached the two crads, doesnt detect on windows 7 64 bits its says error Code 12: This device cannot find enough free resources that it can use, in hardware administration,i put at first the gtx 660 ti but when i used the second pcie the gtx 780 doesnt recognize it on windows and error appears again my mother board says pcie x16 first slot and the second says X8, i need to find is there an issue with that and change the motherboard to an asus sabertooth z77 that has two physical 16 x slots.

[haknslash]

Have you checked if there are any BIOS settings causing you this issue? Perhaps your BIOS needs an update as well?

I did a quick google search for you and it seems there are a few people with this mobo that have run into issues with it recognizing another card in the second PCIe slot. I the solutions were all over the place so perhaps dig around on google and see if any of them relate to your issues.