ASUS TUF Gaming RTX 4080 OC suddenly video signal loss in modern games but not older ones

[ChandlerUSMC]

Computer Type: Desktop. Custom Built 2019

GPU: ASUS TUF GAMING OC RTX 4080. No Overclock (run in default mode). I've always run a global frame limit of 60fps (I run 4K) VSYNC ON (GSYNC) connected via HDMI 2.1 to LG CX

CPU: Intel i9-9900k. No Overclock.

Motherboard: Asus Maximus X Hero. BIOS 2701 (latest)

RAM: Corsair DDR 3200Mhz (2x16GB). XMP Enabled.

PSU: EVGA Supernova 750 G3

Operating System & Version: Windows 11 24H2 Build 26100.4946

GPU Drivers: 581.08

Description of Problem: Ray Reconstruction + Raytracing (modern games) causing video card to lose video signal, create a crashdump and restart the PC. PC has been solid -- no crashes, etc - for years as was the video card (vid card purchased Nov 2022) including modern games and they used to work just fine. Oddly, older raster only games still seem to work fine. I play a lot of older titles so I didn't notice this issue until this week. Was playing through Mass Effect Legendary Edition. No problems. Decided to finally play through Clair Obscur: Expedition 33. Was working fine until a cutscene where you get introduced to camp and blip - loss of video signal, crash dump, restart. Reloaded the game, same issue, same place. So, I load up Cyberpunk (which I've played through completely twice using this video card)- Pathtracing and Rayrecon turned on, etc. Start a new game, create a corpo char, get to the elevator and blip - loss of video signal, etc. Repeatable. I load Hogwart's Legacy (played through that entire game using this video card)- Raytracing + Ray Recon ON. Get to title screen, blip, same. GPU temps when this is all occurring around 62-65 degrees.

Troubleshooting: I tried the latest driver, 581.15. Same result. I tried earlier drivers most using DDU prior (576.80, 566.14, 566.36, 577.00, 580.88). Did SFC, no issue, DISM, etc.

With Cyberpunk, I decided to downclock the memory 100Mhz and it seemed to stabilize Cyberpunk. At least I was able to get past the elevator and I let the game sit for about 20 minutes just "cooking" No restart. Ok. Go back to Clair Obscur. Same problem. So I lowered the power limit to 85% and the core boost clock by 100Mhz. Same problem. So I lowered the power limit to 75%, the core boost by 250Mhz, memory clock by 250Mhz. Same problem.

Ok, this is odd. I was just playing through other games and wasn't crashing. I restore my power limit, core boost and mem clock back to defaults. I load up Assassin's Creed Odyssey. Runs fine. Ok, let's hammer the GPU then. The idea behind this being, if my PSU was starting to fail (it's only 750W), this should expose that. I overclock my CPU to 5Ghz, remove the global FPS limit on my video card and let it cook. AC: Oddysey runs fine for about 40 minutes with the GPU fan blasting over 3000RPM. Try Mass Effect LE. All good. I try Pathfinder: Wrath of the Righteous. No problems.

I bring my CPU back in line, and reinstitute my global fps cap of 60, vsync ON.

Ok, let's try Hogwart's Legacy. Shader compile. Completes and title screen appears. Blip. Video signal loss, crash, restart. I wipe the config for the game to restore to graphics defaults. Game loads up. I load up my old save. Works fine. I quit game and restart it, then turn on Raytracing (game makes you restart). Seems ok. Ran around for about 5 minutes. hmm. Restart, notice that Ray Reconstruction is OFF (missed that because it's in a different menu). Flip it on, apply settings. 3 seconds later. Blip, video signal loss, etc.

One more diagnosis step to try. I've got another custom built Asus X670E ProArt + 7950X3D setup that I've been procrastinating migrating to because I've been running the same Windows installation upgraded over the years but I can use this new system to test my card in a controlled experient.

I pop the card into the new system. install Windows 11 on it using latest ISO. install drivers, etc. Install Steam, Install Hogwart's Legacy. That's all that's now on this 7950x3d system.
Load up Hogwarts, compiles shaders. All good. Turn on Raytracing + RayRecon. Game loads to title screen. Blip! Video signal loss and restart. New system, same symptoms.

What do you folks think has happened to this card?