https://forum.asrock.com/ Copyright (c) 2006-2013 Web Wiz Forums - All Rights Reserved. Fri, 17 Apr 2026 16:02:06 +0000 Tue, 12 Aug 2025 04:01:04 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 12.04 360 https://forum.asrock.com/RSS_post_feed.asp?TID=113292 https://forum.asrock.com/forum_images/web_wiz_forums_black.png https://forum.asrock.com/ https://forum.asrock.com/forum_posts.asp?TID=113292&PID=198707&title=phantom-gaming-b850i-lightning-dual-gpu#198707 Author: Xaltar
Subject: 113292
Posted: 12 Aug 2025 at 4:01am

It sounds more like an OS issue. Multiple GPUs have been problematic from the start
but they have also fallen out of favor lately. By the sound of it, windows isn't
routing the workload and signals properly. If you search "iGPU + dGPU windows issues)
you will see quite a lot of people reporting issues.

To rule out hardware you can try a gaming focused linux distro like Bazzite or
Nobara. If you can get things working right there then the issue is likely down
to the OS and drivers.

Good luck ]]> Tue, 12 Aug 2025 04:01:04 +0000 https://forum.asrock.com/forum_posts.asp?TID=113292&PID=198707&title=phantom-gaming-b850i-lightning-dual-gpu#198707 https://forum.asrock.com/forum_posts.asp?TID=113292&PID=198704&title=phantom-gaming-b850i-lightning-dual-gpu#198704 Author: Yuns92
Subject: 113292
Posted: 11 Aug 2025 at 8:42pm

Hello, I'm Yuns92 and new to this forum. Unfortunately, my English isn't perfect, but I hope everyone can understand me.

I'm having two strange issues with my new HTPC build:
Components:
- Case: Fractal Design Ridge (White, PCIe 4.0, Mini-ITX)
- PSU: Seasonic FOCUS SGX-750 (750W SFX)
- Motherboard: ASRock Phantom Gaming B850I Lightning WiFi
- CPU: AMD Ryzen 7 8700G (boxed)
- RAM: Klevv Fit V 32GB Kit DDR5-6000 (CL28-36-36-76)
- dGPU: Sapphire Pulse Radeon RX 6800 (16GB GDDR6)
- CPU Cooler: Thermalright AXP120-X67 White ARGB

Note: I delidded the CPU, applied liquid metal for better thermals, and insulated the exposed SMD components on the CPU with nail polish to prevent short circuits.

After a fresh Windows 11 install (fully updated), I enabled the EXPO profile in BIOS for RAM overclocking. I have also updated to the latest BIOS version available.

My goal: A dual-GPU setup using "lossless scaling" (dGPU renders games, iGPU handles frame generation).

Problem 1:
When using the motherboard's HDMI output (iGPU), I cannot select 4K@120Hz on my TV. This is unexpected since both the motherboard and 8700G's iGPU support HDMI 2.1. Works flawlessly via the dGPU's HDMI port.

Problem 2 (more critical):
If my TV is connected to the motherboard (iGPU) and I set the dGPU as the default "High-Performance GPU" in Windows, any game launch causes a full system freeze (games, Task Manager, all apps). A hard reset is required.

However:
-> Using the iGPU as default (display connected to motherboard) -> games run fine.
-> Using the dGPU as default (display connected to dGPU) -> games run fine.

Troubleshooting done (no success):
- Updated BIOS to the latest version.
- BIOS reset to defaults.
- Use default speed for RAM.
- Set PCIe Gen to 3.0 in BIOS.
- Increased iGPU VRAM allocation.
- Reinstalled AMD chipset + GPU drivers.

I'm out of ideas. Has anyone encountered this or know a solution?]]> Mon, 11 Aug 2025 20:42:23 +0000 https://forum.asrock.com/forum_posts.asp?TID=113292&PID=198704&title=phantom-gaming-b850i-lightning-dual-gpu#198704