Stuck trying to connect dual RTX 2080TI graphics in SLI setup
Stuck trying to connect dual RTX 2080TI graphics in SLI setup
I recently caused some damage to a PCIe slot on my old machine, so I assembled a new setup from the ground up. It includes a Ryzen 9 7900X processor, an ASUS ROG B650E-F motherboard, and 64GB of DDR5 RAM. For graphics, I’m using two dual Gigabyte RTX 2080 Ti Turbo cards. Before anyone suggests simply selling them for newer models, I’m trying to keep things intact. Getting the two cards to fit was tricky because the PCIe 16x slots aren’t compatible with any available NVLink bridge. I had to use PCIe risers to connect them to an NVLink solution. The motherboard also has two M.2 NVMe SSDs in the top slots. Now here’s the challenge: Windows sees both cards, but in the NVIDIA control panel there’s no way to select one. In GPU settings, the two cards look identical except for a detail—Card 1 uses PCIe x16 at 3.0Gb/s and Card 2 uses PCIe x16 at 3.0Gb/s. That’s confusing since SLI requires both at 8x8 speed, yet the BIOS doesn’t offer a clear setting to adjust this. The only PCIe option is a bifurcation that supports auto, 8x8, or RAID configurations. When I run it in 8x8 mode, one monitor boots Windows on Card 2 while the other stays locked on Card 1. This whole situation feels confusing and frustrating. Any advice would be greatly appreciated. Thank you!
This board doesn't allow SLI functionality, which seems unlikely given the lack of x8 support for GPUs. You'd likely need a board with an x8 slot for both graphics cards and SLI capability, along with a compatible board that has the necessary licensing. Nvidia's stance on this is to charge more for modifications, so SLI remains largely unused. Only benchmarking shows interest, but it's not a major priority. No known AM5 boards have spent resources on SLI since it's no longer practical.
The goal is to maximize performance by using Asseto Corsa on triple monitors for a high-end sim racing rig. Running both cards together can improve stability and resource sharing, potentially boosting frame rates beyond what either card could achieve alone. It’s likely worth trying unless you’re already at peak settings.