7900XTX does not fit into the 16x port.
7900XTX does not fit into the 16x port.
My new 7900XTX isn't posting when installed in the top PCIE port on my MSI X570s Ace Max. It boots normally in other slots, so the problem isn’t with the 16x slot—my old Vega 56 works just fine there. I’ve updated the BIOS, cleared the CMOS, removed all M.2 drives, and still nothing works in the top slot. When I try to run it, I keep seeing post code 94 and BUS Enumeration 32. Any suggestions or advice would be greatly appreciated.
Specs: CPU – Ryzen R7 5800X3D; RAM – 16GB @ 3600MHz; Board – MSI X570s Ace Max; Power Supply – 750W Super Flower Leadex III Gold.
Have you experimented with configuring the slot for manual PCIe Gen instead of automatic settings? Also, have you considered enabling Gen 3?
Also consider covering all lanes on the card once it reaches 8x
I understand you're teasing, but for a 7900XTX the Gen 3 vs Gen 4 gap isn't huge, though Gen 4 compatibility can still pose challenges. I tend to run into more issues with the Auto option than with choosing the right generation. It might just be that manually setting it to Gen 4 and swapping the cards works best. The Auto feature could be confusing because the player is moving from a Gen 3 Vega card to a Gen 4 RDNA3 card, which might affect how the board caches that setting.
I fixed the problem initially, but now the system is very unstable. It crashes and restarts when installing drivers, especially on both GPUs. I’m rolling back the BIOS now. What else should I try?
Hi, I'm facing the same issue too. My MSI X570 Tomahawk Wi-Fi isn't connecting to the router with either the 7900XT or 7900XTX models. I've checked all the online resources I could find, but the only workaround so far is using PCIE gen_3, which makes the system unstable. My previous card (5700 XT) works in both settings. After reaching out to MSI for advice, they suggested several troubleshooting steps—like checking CPU damage, testing with another GPU, resetting the MB, ensuring proper power supply, updating drivers, etc.—but none worked. They recommended contacting the motherboard seller for a professional check-up, which isn't possible since my warranty expired two months ago. It seems like an MSI compatibility problem, possibly fixed in a future BIOS update. I'm not holding my breath and will be searching for another motherboard, preferably non-MSI... I'll keep an eye on this thread for any updates.
Hello, here’s a possible adjustment for you. The auto detection for PCIe buses isn’t functioning correctly on some MSI MBs with the 7900 GPU, so you’ll need to configure it manually. Follow these steps:
- PCI_E1 Gen Switch: gen4
- Chipset: PCI_E Gen Switch
- Lane configuration: 4x+4x+4x+4x
I didn’t set the lane config before changing it, and after doing so, the board passed through and worked well. I’m not certain about the exact names of the settings, but you should be able to locate them.
Regarding PCIe bursting, I added a little configuration to it. It seems it can split lanes in a PCIe slot or more than one. However, I’m not sure how it impacts your graphics card performance—anyone have insights?