Cannot Enable SLI in Windows for Pair of GeForce GTX 660s
Posted on 2014-11-08
Hey Guys -
I've got a home system with the following specs:
- Intel i7-3770k CPU
- 16gb of RAM
- Gigabyte GA-Z77X-UD5H Motherboard
- Dual Nvidia GeForce GTX 660 (Latest Drivers are installed)
Note: One has 2gb RAM and the other 3gb
- Hardware SLI Bridge connected to both video cards
- Windows 8.1 Update 1 x64
I bought the 2GB about 6 months ago when I got my Shield and the 2nd one which is 3gb about a week ago. When playing around with benchmarks, I downloaded and opened GPU-Z to see that SLI wasn't Enabled. I opened Nvidia Control Panel, but the option to enabled SLI wasn't even there. Both cards do appear individually in the Nvidia Control Panel and Device Manager.
After a bit of research, I ensured everything was up to date and reseated the cards. I even found and tried a post where I had to add 4 DWORD registry entires. The option still doesn't appear.
I dug through the BIOS and the only video setting I saw was for if the internal one was enabled/disabled. I tried both settings. I also found a post that said during POST hit Ctrl-F1 which would show "hidden" options which I usually wouldn't see since I don't currently use UEFI, but that didn't do anything. I went to Gigabytes site and downloaded the GA-Z77X-UD5H manual. It has a page about SLI but in the Nvidia Control Panel settings, it says just to make sure "Maximize 3D Performance" was enabled.
For a minute, I thought that perhaps in newer driver versions and/or in Windows 8.1, there was no option and SLI would automatically be enabled. However, if so I don't think that GPU-Z would have shown SLI as "Disabled."
Any ideas or suggestions? Thanks!