[FrothyOmen]

Hi everyone. Bought an EVGA GTX 770 2GB Superclocked around this time last year. Somebody just donated to me an EVGA GTX 770 4GB graphics card with a blower style cooler and lower base clock/memory clock speeds.

I have connected both cards to my Gigabyte Z87X-UD3H Motherboard, and both cards are confirmed to be plugged into the correct PCI-e slots. The SLI Bridge is confirmed to be installed correctly and appears functional. I have an RM850 PSU, so, power should not be an issue in this build.

My problem is that the Nvidia Control Panel (NVCP) is not giving me the option to switch my GPUs into SLI mode. It is my understanding that even if you have two GPUs of different VRAM sizes, they will still SLI at the lower VRAM amount so long as they are in fact the same GPU, which they are, they are both GTX 770s.

I am struggling to even get NVCP to give me the option to enable SLI. Usually, the option is either greyed out or completely unavailable for me to choose.

Here's what I have attempted so far to fix this issue:

• Verify Integrity of all connections, verify GPUs both appear in device manager/NVCP (they do), verify that both GPUs operate when put in primary slot (tested with Valley)
• Swap locations of the two GPUs on the motherboard.
• Boot the system with SLI Bridge not installed, reinstall drivers, power down and install SLI Bridge, reboot. (In this scenario, NVCP changes from not offering me any SLI options at all to showing SLI options and greying them out, not allowing me to interact with them)
• Many other permutations of clean driver installations with/without SLI bridge installed/GPU location configurations.
• Coolbits registry tweak fix will actually enable the correct SLI option (something like maximize 3d performance) and let me pick it. However if I pick this option and try to apply, whatever process Geforce Experience tries to run in order to activate my SLI hangs and fails at about 25% progress, and actually necessitates a complete clean reinstallation of my drivers every time. In addition, this clean installation overwrites my Coolbits registry edit. Here is a screenshot of the hang: http://i.imgur.com/PrCzgu6.png?1

I am at a loss for how to proceed from this point. I would feel terrible if this guy donated such a powerful GPU to me for it to end up being completely unusable. My GPUs are currently configured in what I would consider to be "backwards" order, with the blower being first below the CPU, then the open cooler below it. I switched to this configuration because I had read online that putting the 4GB card first would enable you to SLI it with your 2GB card, obviously this isn't the case so I'd like to switch the configuration back if possible so I have more optimal cooling performance on both cards.

Can any Nvidia gurus help to get me running? :\

System info:

WIndows 8.1
4670k
EVGA GTX 770 2GB SC
EVGA GTX 770 4GB
Corsair Vengeance 2x8GB
Crucial Ballistix 2x4GB (24GB RAM total)
Gigabyte Z87X-UD3H
Corsair RM850
Toshiba 1TB HDD
Samsung 840 EVO 128GB
QNIX QX2710LED 1440p/120Hz + Samsung SyncMaster (lol) 1080p/60Hz

Geforce Experience drivers are up-to-date and have been clean installed many times.
GPU-Z and Device Manager and NVCP both report seeing two GTX 770s.

 

[MR KROGOTH]

You've reinstalled drivers?
Checked GPU-z, and Device manager to see if the second card is recognized?

 

[FrothyOmen]

Quote:

Originally Posted by MR KROGOTH

You've reinstalled drivers?
Checked GPU-z, and Device manager to see if the second card is recognized?

Both cards recognized and operate independently. I am just not getting an option to enable SLI, and if I perform registry edits to make that option available to me, the "SLI Enabling" process hangs and fails every time, breaks my drivers, and forces a complete clean reinstall.

Proof: http://i.imgur.com/exxl0W8.png

 

[MR KROGOTH]

Tried disabling onboard GPU in BIOS?

 

[recoton]

Are you using hypersli or other patchs from techpowerup?different sli works with 344.60 so i seen on a thread otherwise 335.23only works with the hypersli .96 and the only way i got it to work was install his sli patch then update the ,o96 hypersli exe and then it worked fine.Im running on a p35 chipset.