780Ti's do not seem to be running in SLI

[Paladone]

Hey,

Today I decided to clean up my PC and afterwards ran some benchmarks to ensure that everything was functioning properly. However, when I ran a Unigine heaven 4.0 Benchmark, I only got a score of 1664 (half of what I was getting before). I was wondering therefore if anyone has any idea why this might be the case?

The settings I had were:

API: DirectX 11
Quality: Ultra
Tesselation: Extreme
Resolution: 1920*1080p fullscreen
Anti-aliasing: x8
Stereo 3D disabled
Multi-monitor: disabled

My graphics cards are two 780Ti's, overclocked to 1125Mhz (1250 with gpu boost) and I have driver version 353.30. I am not sure if it matters, however I also have three monitors, two (including the main monitor) plugged into the first card (with DVI) and the third into the second card (with hdmi).

Thanks

 

[newtekie1]

Obviously, you've checked to make sure SLI is enabled in the nVidia control panel, right?

 

[Paladone]

Obviously, you've checked to make sure SLI is enabled in the nVidia control panel, right?

Yeah, SLI is definitely on. Unigine heaven had also registered both to be running.

 

[blobster21]

What kind of clean up exactely ?

 

[Paladone]

What kind of clean up exactely ?

I had simply cleaned up all my files, uninstalled a lot of unneeded programs, run a virus scan and used compressed air to clean my radiators.

 

[MxPhenom 216]

Update drivers and do it by doing a clean install. Uninstall your current drivers from windows control panel, Get Display Driver Uninstaller app, boot to it in safe mode, select NVIDIA, and clean. Reboot install new 355.98 drivers, and also check off the "Clean Install" box.

 

[newtekie1]

Use something like MSI Afterburner to see if both GPUs are being used under load and both are clocking up to full speed under load as well.

 

[cadaveca]

Use something like MSI Afterburner to see if both GPUs are being used under load and both are clocking up to full speed under load as well.

Afterburner doesn't like the 780TI much. EVGA Precision is the tool to use with those cards.

I'd say it was a driver issue, but I have talked to a couple of other SLI users that have had issues lately after a Windows update, so the best bet is to re-install drivers and then see what happens. My cards are working fine in Win10 on the most recent driver, although that doesn't say much.

 

[newtekie1]

Afterburner doesn't like the 780TI much.

Now that I think of it, considering the site I'm on, I should have recommended he use GPU-z.