I'm trying to add a second GPU to my existing setup, but I'm running into some issues. Here's my setup:
- Motherboard: B450 MSI Tomahawk (NON MAX)
- CPU: 5800X3D
- GPU1: Nvidia RTX 3090
- GPU2: Radeon RX 580
- RAM: 48GB 3200MHz
- Storage: 2 SATA SSDs, 1 M.2 SSD
With only GPU1, everything works perfectly. However, when I install GPU2, my PC starts, but there's no video output. If I remove GPU2, I need to reset the BIOS to use GPU1 again. I'm looking for advice on how to get both GPUs working together.
Also, I know that GPU2 might block airflow for GPU1, so I've ordered a PCIe riser cable to position GPU2 outside the case. I tested GPU2 when I bought it, so it's functioning. What can I do to make this setup work?
1 Answer
Have you tried connecting your monitor to GPU2 directly? Sometimes the output can switch to the second GPU when both are installed. Also, check if there's any POST error display on your motherboard when you boot with both GPUs.
It sounds like GPU2 might not be compatible with your motherboard when both are installed. Have you tried updating the motherboard BIOS? Sometimes compatibility issues can be resolved with a firmware update.
I did connect the monitor to GPU2, but I still didn’t get a signal. I noticed some debug lights as well, and I'm curious if they're indicating something wrong with the installation.