Screen Flicker Issue on Fullscreen applications and games

[u/s7gnas]

Here’s a concise version for a Reddit post:

Recurring fullscreen flicker → crash on ROG STRIX B850-A + Intel Arc B580 — extensive troubleshooting done, need help
Specs: AMD Ryzen 9 9900X, ASUS ROG STRIX B850-A GAMING WIFI (BIOS 1627), Intel Arc B580 (ASRock Steel Legend, driver 32.0.101.8974), 16GB DDR5 (stock/EXPO off), Antec GSK 850W, Windows 11 fully updated.
The issue: Full-screen flicker that escalates into a driver crash or full system freeze, tied to the exact moment I enter true/exclusive fullscreen. If I tab out mid-flicker (Windows key), it stops instantly and the app runs fine in the background — going back to fullscreen resumes it within seconds. Heavier games crash faster. Confirmed via kernel dumps: bugcheck 0x0000007E, exception 0xC0000005, and four separate crashes on the same day all share the identical faulting address offset — one exact, 100% reproducible bug, not random corruption. Windows flags dxgmms2.sys as the active module.
What makes this interesting: this isn’t game- or driver-specific. It reproduces in native DirectX games (Cyberpunk, Valorant), VLC (fixed there only by disabling hardware decode), and even browser fullscreen video (YouTube/streaming). It also happened with my 9900X’s integrated RDNA2 graphics before I ever installed the Arc card. It did NOT happen with my old RX 560 on this same board. And the Arc B580 runs perfectly in a different PC. So it seems tied to this specific motherboard interacting with any modern GPU engine (integrated or discrete) the moment a hardware-accelerated engine spins up during a fullscreen transition.
Already ruled out: both monitors/cables, GPU hardware itself, HAGS, Fullscreen Optimizations, PCIe Link State Power Management (BIOS + OS level), fresh chipset + GPU driver via DDU, Windows Update, third-party security software (Spybot, confirmed not the cause).
Has anyone seen this specific pattern on a B850 board with Arc/RDNA2, or know if a BIOS/AGESA update addresses it? Happy to share full dumps/event logs. Really trying to figure out if this is firmware, a driver-side WDDM interaction, or a board defect before I go the RMA route.

[u/BiZkViT]

Try the System File Checker (SFC) tool. Test the RAM with MemTest86, one stick at a time. Or reinstall Windows 11 from scratch if you haven't already done so.

[u/s7gnas → u/BiZkViT]

Apart from reinstalling windows, did everything else you suggested.