Neo G8 4K 240Hz losing connection randomly for 1-2 sec

[Byogore]

Have a problem that kind of makes no sense to me. I swapped from an RTX 4090 Suprim to 5090 FE and now the monitor randomly turns off for 1-2 sec and recovers. Tried 3 different cables (Silkland DP 2.0 and IVANKY) also the default cable. All of these cables worked fine before. I am using the latest firmware.

The monitor wasn't even used at all after I sold the 4090. I just plugged it in after a month. When using GSYNC, this blackscreen never happens. When you turn off GSYNC (aka adaptive-sync on the monitor's settings), you lose connection to the monitor for 1-2 sec whenever it feels like it. Could be 1 minute, 15 minute or 30 minutes. This happens on desktop and in games. Monitor goes black and in the top left you can see the Display Port icon, as if I manually reconnected. Stock 5090 settings. You don't need to use GSYNC in NVIDIA Panel, you just need to have Adaptive-Sync enabled on the monitor (in case you don't want to use GSYNC but want to fix the issue)

I never had these black issues before with adaptive-sync off. Windows is fresh, DDU drivers multiple times, tried the last 4 drivers and it still happens on 572.83. I also tried the 1080p 240Hz BENQ that I have here and it didn't cause any blackscreens (didn't test it much tho) but I am guessing this is a driver issue with DSC and for some reason "Adative-Sync" set to enabled on the monitor the issue go away.

So what do I do now? RMA the monitor or is the GPU broken? It's hard to tell what's happening here. The GPU works fine under any stability test (3DMark etc) with max OC, heavy undervolt and also stock. Tried all ports (except HDMI since I don't have an HDMI cable atm but will soon)

Waiting on a SILKLAND 2.1 DP cable to try that. Edit: didn't do anything (not that I was expecting it to, wanted the cable anyway)

What a frustrating issue. Specs below

CPU: 9800X3D

GPU: RTX 5090 Founders Edition

Motherboard: X870E Nova (3.15 BIOS) and using PCIe x16 5.0 (tried 4.0, still the same thing)

PSU: NZXT C 1500W

Windows 11 latest build.

Edit:

576.02 - no fix.

576.26 Hotfix Driver - no fix.

[Samsung_WDeOgeN]

I have the same problem with my Gigabyte 5080. Its only an issue with 4k and 240hz. The reason it doesn't happen with adaptive sync is because you aren't hitting whatever threshold (somewhere above 120hz) where this becomes an issue. If you play a game with 240 fps I'm sure it will pop up again. I've had no help from Gigabyte support or Nvidia, they just keep having me test my config and try the new drivers. They hoped the Hotfix would fix it but no. Consensus seems to be that it is a driver issue. Maybe it is maybe it isn't. Not sure If I'm going to be able to get Gigabyte to RMA me for a new one if it is hardware, so far it can't be proven. There are no crashes so now crash or error log to pull. 

Also didn't have the problem with my 4080, so it looks like its something to do with the drivers and spans across multiple companies. I am guessing it isn't super prevalent because those of us with 240Hz monitors and 5000 series GPUs is probably a pretty small group.

Anyway, my point is its probably a driver issue and if not then its a hardware issue spanning multiple companies so the fault would lie in a common faulty component. I'm betting on driver.

[Byogore]

I've tested it in multiple games for weeks now - no blackscreen at any FPS, doesn't matter if it's 300 or 600++ in competitive shooters. Never happens with adaptive sync on. This is some weird bug that Samsung will have to figure out with NVIDIA. I'm guessing a bug with DSC.

This issue also happens at desktop just as frequently (when not using adaptive sync) so it's probably DSC related when using 240Hz.

[matthewaasi]

Interestingly, after thinking the issue was fixed yesterday, i just had a flicker once this morning. Still, it's FAR less frequent than is used to be. But frustrating nontheless. Hopefully we can get a fix soon - I'm about to go out and buy a new monitor.

[Samsung_WDeOgeN]

They just came out with 576.28 which specifically states that it fixes the DP2.1 with High refresh rate issue. So fingers crossed this one actually fixers it!

[Samsung_WDeOgeN]

It just did it to me twice while in windows so I guess not..........

[Byogore]

I already tried it earlier, it's still broken. Happens in games and desktop.

[pacolotero]

same here, with 5090, change to a 2.1 display port cable and still the issue. Gsync on/off, VRR on/off, Adaptative sync on/off all the combinations

[jwfitt]

Same exact issues on Samsung G9 Neo Odyssey 57" (G95NC) with RTX 5090. Have tried all drivers (cleaned with DDU in Safe Mode first before installing new ones), supplied cable, silkland DP80 2.1 cable at 6.6', 10' and a few other 2.1 cables.

[pacolotero]

I had my main monitor connected to DisplayPort 4 on the graphics card, and after switching it to DisplayPort 1, the issue hasn’t happened again in the last 3 days. I also changed the secondary monitor from DisplayPort to HDMI because I read that DSC shares bandwidth between DisplayPorts. I’ll keep you updated.

[Byogore]

Gave HDMI a try and all issues are gone, even with adaptive sync off (made sure it's set to 4K 240Hz, it was set to 120Hz when I swapped to HDMI). For those who haven't read my previous comments, adaptive-sync set to ON (on the monitor) fixes the blackscreen / disconnecting issues for me while using DP, but don't want to use adaptive-sync, just like I didn't in the past on the 4090. Now with HDMI I can turn it off again. So give HDMI a try, seems DP is just broken.

Still no info from NVIDIA or Samsung. Amazing support.