System Overview
- Motherboard: MSI X99A SLI PLUS (MS-7885)
- CPU: Intel Xeon E5-2697Av4
- BIOS Version: 7885v1F2(Beta version)
- GPU (Old/Working): ASUS RX 5700 XT OC 8GB [also used for BIOS access]
- GPU (New/Problematic): Gigabyte 9070 OC 16GB
- RAM: 32GB DDR4
- NVMe SSD: Present (removed during troubleshooting)
- Monitor Connection: Verified directly to GPU during tests (used only HDMI)
Problem Description
- The new Gigabyte 9070 OC 16GB GPU is not detected by the motherboard (no POST, no display output, not visible in UEFI). 1 long, 2 short beeps.
- The old GPU works and allows access to BIOS.
- Goal: Get the new GPU recognized and working on the X99A SLI PLUS.
Steps Already Taken
1. BIOS Settings Adjustments
- Enabled “Above 4G Decoding” in BIOS.
- Set PEG2 (PCI_E1/E5, primary GPU slot) to “Gen3” (instead of Auto) to force PCIe 3.0 compatibility.
- Left PEG0 and PEG1 on “Auto”.
- M.2 Source Link: Set to Auto.
- M.2 PCH Strap: Set to M.2 PCH SATA.
- PCI Latency Timer: 32 PCI Bus Clocks (default).
- Screenshot of current settings attached:
![BIOS Screenshot]1
2. Hardware Troubleshooting
- Removed NVMe SSD to eliminate PCIe lane/resource conflicts.
- Reseated GPU and verified all power connections.
- Tested monitor and cables directly to the new GPU.
3. BIOS/UEFI Maintenance
- Updated to latest available BIOS for the motherboard.
- Cleared CMOS and reapplied settings after changes.
- Tried both UEFI and CSM/Legacy boot modes (where available).
4. Other Attempts
- Tested the new GPU in another system to confirm it is functional.
- Tested other PCIe slots on the motherboard.
Results
- No detection of the Gigabyte 9070 OC 16GB GPU in any configuration.
- Old GPU continues to work, confirming the motherboard and slots are functional.
- All recommended BIOS settings for modern GPU compatibility (Above 4G Decoding, PCIe Gen3, NVMe removal) have been tried.
- No success with toggling CSM.
- No POST or display output with the new GPU installed.
Request for Help
- Suspected Issue: Fundamental compatibility problem between modern UEFI-only GPUs and the X99A SLI PLUS (MS-7885) BIOS/firmware.
- Seeking:
- Modded or unlocked BIOS for MS-7885 that exposes additional PCIe or UEFI settings (e.g., IntelRCSetup menu, advanced MMIO/PCI resource options).
- Guidance or files from users who have successfully run modern GPUs (RDNA3/4, RTX 40 series, etc.) on X99A boards.
- Any further troubleshooting steps or BIOS modding advice.
Screenshot of current PCI Subsystem Settings:
![BIOS Screenshot]1
Thank you for any assistance or shared experience!
—1: https://pplx-res.cloudinary.com/image/upload/v1746383179/user_uploads/34140370/RMybpaqUwCrHlEk/selected_image_5368676460161664951.jpg
Edit by Fernando: Thread title customized and shortened
