GA-Z68XP-UD3 PCI Express issues

[Chunka666]

Hey all, I have a GA-Z68XP-UD3 on F2 BIOS which doesn't want to display any output on my Palit GTX 770 through the PCIEx16 slot, I can boot into windows but device manager doesn't find anything, all fans are spinning and it appears to running normally.
I have tested the GTX 770 in the PCIEx8 slot and it runs fine (probably limited in performance mind you) GeForce experience also finds it and all drivers are clean installed and up to date
I have today tested a GT210 in the PCIEx16 slot and it runs fine, device manager displays it, drivers installed fine no issues.

First question, aesthetically the system looks quite nice with the GTX 770 on the bottom row, but does the PCIEx8 impact its performance that much?
(I'm getting 80FPS avg on PUBG with 0.1% 50FPS)

Second question, (other than updating BIOS, cannot get gigabytes updated to run atm) can anyone think of a reason that the GTX 770 doesn't even show up in the device manager but the GT210 does in the PCIEx16 slot?

SYSTEM SPECS:
i5-2500K @4.3 1.22v (was running at 4.5 but lowered to do some testing)
GA-Z68XP-UD3 F2 BIOS
8GB KINGSTON 1600Mhz RAM 9-9-9-24 1.5v
Palit Microsystems GTX 770 (stock settings)
OCZ SSD - Windows installation drive
500GB WD Green
Corsair 750CX 80+ Bronze PSU

 

[Zerk2012]

Their no performance difference in X16 and X8 as that card can not saturate a X8 lane.
Not a clue why the 210 would work and the 770 will not.

 

[Chunka666]

Their no performance difference in X16 and X8 as that card can not saturate a X8 lane.
Not a clue why the 210 would work and the 770 will not.

Thanks for the response, good to know that the GTX 770 won't be affected, just out of curiosity how high can I go before the cards over-saturate the slot?(would I 970/980 not work), yeah I can't figure out why, I eliminated the BIOS problem with an update but no change to the 16x slot

 

[velocityg4]

Download the latest nVidia drivers. During installation. Choose the option to perform a clean install. Sometimes that will clear up the issue of the video card not being found by the Device Manager.

 

[Chunka666]

Download the latest nVidia drivers. During installation. Choose the option to perform a clean install. Sometimes that will clear up the issue of the video card not being found by the Device Manager.

I have tried that, nothing shows up, it remains the same with only the HD3000 showing up. and the driver installation failing.