PC Graphics

[jt876]

Hello,

I'm having some trouble with iGPU and dGPU, not sure if the problems are related.

1. I can't disable iGPU or enable CSM in BIOS, it will not post and settings will revert back. HWInfo shows the iGPU consuming over 20W even when dGPU is used, could this also affect the performance of the CPU?

2. dGPU shows as PCIE v4.0 x16 @x8 despite no other component sharing the bus. Is it shared with iGPU?

3. After reset/restart dGPU is not detected and motherboard VGA LED will remains lit. Display image is only available from iGPU. No issues after power cycling though, then dGPU shows image. This only occurs with 4090, old gtx 960 has no problems. This has happened on two different 4090s. I've tried all ports DP and HDMI on the GPUs, tried reseating, forcing different PCIe settings, different monitors. I have not tried the other slot on the motherboard because there is no room in the small case.

My motherboard is ASUS ProART X670e with 1303 BIOS.

I haven't heard back from ASUS support yet, could this be an issue with the CPU itself?

[jt876]

I should add that for problem 3. I can hear that the PC boots to windows, only no image and VGA LED stays lit. Connecting iGPU to monitor will give image, but dGPU is not recognized by device manager either.

[jt876]

I noticed that when using GTX 960, I can disable the iGPU. However, the GPU shows up as PCIe 3.0 @x8 instead of x16, so to me it seems there is something wrong with the motherboard.

[Matt_AMD]

1. I tested this on my 4090 and I was able to disable the iGPU in the BIOS and post without issue. . I am using the X670E Hero board and the option (to disable iGPU) can be found under the Advanced BIOS > PBS menu. However if I removed the 4090 and only used the iGPU, disabling CSM caused a no display output. Keep CSM disabled and iGPU worked fine. 

2. No.

3. Probably best to reach out to the motherboard manufacturer and Nvidia for support with this issue.