Instability with two GeForce GTX 670 and PCIe Gen3


I’m experiencing stability issues and Xid errors on heavy graphics load like three instances of the Heaven Benchmark running in parallel. The errors occur when the PCIe speed is set to Gen3 in the UEFI setup. When forcing Gen2, the system seems stable. When the error occurs, the graphics will usually hang completely, but I am able to log into the system remotely.

The two graphics cards are configured to run in base mosaic mode and the X screen spans three monitors. I’m currently using driver version 319.32, but I was able to reproduce the issue with the 325.08 beta driver as well.

I have attached a NVIDIA bug report that was created right after triggering the problem.

System specs overview:

OS: Arch Linux, Kernel 3.10.3
GPUs: 2x EVGA GeForce GTX 670 FTW, 4 GB RAM
Mainboard: ASUS Z87-WS
RAM: Corsair Vengeance LP 32 GB DDR3-1600 (4 DIMMs)
CPU: Intel Core-i7 4770K, 3.5 GHz
PSU: be quiet! Dark Power Pro 10, 1000W

The BIOS of the mainboard and graphics cards are updated to the latest versions.
nvidia-bug-report.log.gz (117 KB)