Zenbook Pro Duo UX582 - External Monitor Refresh Locked at 30p

[Mnixon76]

System: Zenbook Pro Duo
Battery or AC: AC
Model: UX582
Frequency of occurrence: every time
Reset OS: Latest Windows 10
Screenshot or video:
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Detailed description：I'm trying to output my Zenbook Pro Duo UX582 system to a Dell U4021QW which is 5120 x 2160 resolution. The max refresh rate I can get when plugged in either via HDMI or USB-C Thunderbolt is 30Hz instead of 60Hz. I've tried a a variety of cables, reinstalled video drivers...nothing helps. If I drop the resolution down to anything less than the native resolution 60Hz is available but not at the native screen resolution of 5120 x 2160. I would think it could support considering USB-C Thunderbolt 3. I've tried using the screen as an extended screen and as my only screen with the laptop lid open and closed. No difference.
Monitor specs show: Native Resolution
WUHD 5120 x 2160 (DisplayPort: 60 Hz, HDMI: 30 Hz)
But why wouldn't this work using the USB-C Thunderbolt ports which are advertised to support DisplayPort connection, and the 40 Gbps bandwidth lets you connect an external 8K display or two 4K UHD displays.
Any suggestions? Thanks!

[Blake_ASUS]

Hi there,
May I have the complete model name? Is it UX582LR?
Thank you.

[Mnixon76]

Yes that’s the model thanks for looking into it !

[Blake_ASUS]

Hi Mnixon,
Let me consult more about this issue.
I will keep you updated.
Thank you.

[Mnixon76]

Is there a way to divert the external thunderbolt display through the Nvida 3070 RTX instead of the Intel UHD 630? Some laptops allow that through a bios setting. I couldn't find an equivalent setting in the UX582 bios.
My reason is as follows:
The Dell U4021QW accepted 60p at the full resolution from my Dell G15 Gaming Laptop via USB-C at 60p through Nvidia 3060 graphics card.
On this Asus UX520 the output from the Thunderbolt/USB-C ports is via Intel UHD integrated graphics according to what windows reports.
When I research the output capabilities of the Intel UHD integrated graphics (Intel UHD Graphics 630) it says it can handle 4096x2304@60Hz Max.
Intel added support for Ultrawide resolutions but the 5120 x 2160 resolution I bet is too much bandwidth for the internal intel UDH 630 graphics to handle 60p so it maxes at 30p.
I connected the same Dell monitor using the HDMI connector on the Asus UX582 and it showed that it the output was coming from the Nvidia 3070 GPU and I was able to force 60p (although my monitor maxes out at 30p via HDMI so the image wasn't fuzzy). If only the Dell U4021QW accepted 60pm via HDMI then the issue would be solved - instead it only accepts 60p via it's Thunderbolt input.
In conclusion, the problem appears to be the limited output capability of the Intel UHD Graphics 630. But the Nvidia 3070 could handle this resolution and 60p refresh rate since the 3060 could.
So again, is there a way to divert the external thunderbolt display through the Nvida 3070 RTX instead of the Intel UHD 630 on the UX582?

Thanks!