SLI not showing up as available

[EnderDragoon]

I have a pair of GTX980s that I moved from a Hero VII to a Hero VIII and now I've lost SLI. I am running the same Nvidia drivers on both ends, 347.25 (I know it's a slightly older driver but it's the newest driver compatible with 2x2 surround on the Samsung monitors I'm using). Dug through the BIOS and I'm not seeing anything regarding SLI. Updated to 1302, 6700K, 2x EVGA 980, Hero VIII, GSkill 4x4G 3000, EVGA 1200watt PSU, Samsung 950 Pro m.2. Anyone else having problems with SLI on the Z170 boards? Yes I've tried several other SLI bridges, I actually have 2 on there right now with no luck, tried just one on front and one on back with no help, tried just 1 monitor on top card or 1 monitor on bottom card and I'm not getting any SLI options.

[Chino]

When you say you're not getting any SLI options, are you referring to the option to activate SLI that's located in the NVIDIA control panel? Also are you using a fresh Windows installation or a previous one?

As a sidenote, please list your complete system specifications and indicate which slots you're using for the GPUs.

[Nate152]

Hello EnderDragon

Check in the bios to see if both gpu's are recognized and running at x8. Check in device manager and NVidia control panel to see both 980's are listed there too. Do you have a sound card or anything else installed in the pcie slots?

Connect your monitor cable to the first gpu which would be the top one, make sure the sli bridge is connected and try the latest driver. After you install the driver it should say your machine sli capable, click on the notification. I'm sure you know all this as you've had it working before. 🙂

This is for windows 10 - 64 bit.

http://www.nvidia.com/download/driverResults.aspx/96883/en-us

I do a custom/advanced install, after the license agreement click custom/advanced install and uncheck everything except the graphics driver and the PhysX driver, then just below that check the only box that says perform a clean installation.

[EnderDragoon]

Thanks for the replies. I can try the latest driver for Nvidia to see if SLI is at least recognized but I have been back and forth with Nvidia regarding their inability to recognize these Samsung 4k TVs for months now and the latest driver that supports Surround with them is 347.25 (which also means I'm stuck with regular 980s instead of the 980 TI). If I go any newer the custom resolutions list is not populated rendering the newer drivers useless to me. This is a professional flight simulator we're trying to migrate to newer tech so just going to W10 is not an option as most of the flight software is only fully compatible with 7.

GPUs in BIOS are both detected and showing as x8. All ports on the video cards are able to output to the monitors. In fact I can have all 4 plugged in (2 on each card, DVI and HDMI) and get an extended desktop across all screens but 2x2 Surround is required for this design. When going into the Nvidia Control Panel where it normally says "Configure SLI, Surround and PhysX" it only shows "Configure Surround and PhysX" and the typical "SLI" bar across the bottom that shows the 2 cards running in SLI is not there along with the relevant options for SLI.

The 2x 980 (04G-P4-2980-KR) are in PCIe slots 1 and 2. Is it possible that using the M.2 950 Pro drive could be interfering with SLI? Windows install is fresh as of yesterday. Is this motherboard not compatible with SLI on the 347.25 Nvidia driver (worked fine on the Hero VII, don't know how substantial the difference is)?

I attempted re-installing the 347.25 driver as a "clean install" and always uncheck the 3D drivers as well as Nvidia Experience as it's annoying and useless for professional applications. Also attempted using Display Driver Uninstaller to really clean the system and performed a fresh re-install of video drivers with no luck.

ASUS ROG MAXIMUS VIII HERO
2x EVGA 980 - 04G-P4-2980-KR
EVGA 220-P2-1200-X1 80 PLUS Platinum 1200 W
Intel Core i7-6700K 8M Skylake Quad-Core 4.0 GHz LGA 1151
G.SKILL Ripjaws 4 Series 16GB (4 x 4GB) 288-Pin DDR4 SDRAM DDR4 3000 F4-3000C15Q-16GRBB
SAMSUNG 950 PRO M.2 256GB PCI-Express 3.0 x4 Internal Solid State Drive (SSD) MZ-V5P256BW
Windows 7 64

[NemesisChild]

I'm not sure how a 980 would differ from 980Ti's when it comes to custom resolutions.
I would first try a newer Nvidia driver to see if you can activate SLI in the NVCP.
The M.2 950 Pro could possibly be playing havoc on the PCIe lanes but it's doubtful.

Are both 980's showing up in Device Manager and GPU-Z?

[EnderDragoon]

NemesisChild wrote:
I'm not sure how a 980 would differ from 980Ti's when it comes to custom resolutions.
I would first try a newer Nvidia driver to see if you can activate SLI in the NVCP.
The M.2 950 Pro could possibly be playing havoc on the PCIe lanes but it's doubtful.

Are both 980's showing up in Device Manager and GPU-Z?

Both 980s show up in device manager, both work and can output video feeds through all ports. Every version of the 980TI's *drivers* dont support the monitors I'm using. The newest driver that does work is 347.25 and it incompatible on the 980TI. I have even modified a version of the 347.25 driver to make the TI compatible but it was very buggy. At first chance I will attempt to use the more recent drivers to see if at least SLI is functional even if Surround is still broken. The sim is on the road going to trade shows and will be back on monday.

[Menthol]

The M.2 drive is tied to pcie 3.0x4 slot, which is off the pch controller, slots 1 and 2 are off the cpu so the M.2 drive does not interfere, is the OS a fresh install or did you carry it over from you last system, I would update the Intel chipset driver, use DDU to clean out all Nvidia drivers and install Nvida drivers again
And as Nemesis asks, do they both show in device manager and GPU-Z

[EnderDragoon]

Menthol wrote:
The M.2 drive is tied to pcie 3.0x4 slot, which is off the pch controller, slots 1 and 2 are off the cpu so the M.2 drive does not interfere, is the OS a fresh install or did you carry it over from you last system, I would update the Intel chipset driver, use DDU to clean out all Nvidia drivers and install Nvida drivers again
And as Nemesis asks, do they both show in device manager and GPU-Z

Yes the OS was freshly installed for this build just hours before it was discovered that SLI is not working (as I discovered this while building the rig from all new parts and fresh W7 install). I did try to use DDU and reinstall the drivers but it was little difference from a fresh W7 install with just 347.25 Nvidia drivers.

The only thing that's a little out of ordinary is due to the M.2 drive not having native NVMe support in W7. I had to install to a typical SATA SSD and use the Samsung Migration Tool to mirror the drive over to the 950 Pro. I dont see how this could be an issue but I will attempt to move back to the SATA drive and see if that affects it.

[Chino]

Have a look inside Device Manager and see if the GPUs are installed properly.

[Chino]

Sounds like a long shot but have you tried swapping PCIe cables? Or testing with another PSU?