EnumAdapters often enumerates default adapter twice on multi-GPU PC

Suguru Kitsuki 6

My PC has two graphic cards, RTX A4000 and RX6400.
But EnumAdapters enumrates 3 graphic cards. A4000, RX6400 and A4000

example code:

Microsoft::WRL::ComPtr<IDXGIAdapter1> adapter;
for (UINT adapterIndex = 0; S_OK == factory->EnumAdapters1(adapterIndex, &adapter); ++adapterIndex) {
DXGI_ADAPTER_DESC1 desc;
if (adapter->GetDesc1(&desc) == S_OK && (desc.Flags& DXGI_ADAPTER_FLAG_SOFTWARE)==0) {
wprintf_s(L"%u:%x-%05x: %s\n", adapterIndex, desc.AdapterLuid.HighPart, desc.AdapterLuid.LowPart, desc.Description);
}
}

output:
0:0-0fca0: NVIDIA RTX A4000
1:0-11bf6: AMD Radeon RX 6400
2:0-1b89e: NVIDIA RTX A4000

Why is default graphic card RTX A4000 listed twice when there is only one?
I tested on some PC and multiple GPU combinations, 2080Ti, RTX3070, RTX3060.... and encountered this problem with high probability.
There is no problem if the PC has only one GPU.
DxDiag also reports the default graphic card twice on multi-GPU PC.
I think this problem has occurred since Windows 10 1903～1909.

David Lowndes 4,711 Reputation points

2022-08-07T13:18:00.653+00:00

As you can reproduce this issue with DxDiag, and if you have the latest certified drivers for these cards installed, unless someone else is already aware of this issue, I think you probably need to report it to Microsoft using the telephone support channels available to you.
Another avenue would be to see if any Nvidia or Radeon support forums are aware of this.
Junjie Zhu - MSFT 17,226 Reputation points Microsoft Vendor

2022-08-08T07:45:31.093+00:00

Hi @Suguru Kitsuki
Welcome to Microsoft Q&A!

Because my computer only has an integrated graphics card, I can't reproduce your problem for the time being. So I have some questions I need to confirm with you.
1. Is this question going to come up every time you take a test?
2. Whether the same problem can be reproduced on other computers?
Your replay will be greatly appreciated.

Junjie

Alden Pang 0

I also met this problem on directx12 with rtx 3090 on driver 31.0.15.2802, only 1 physical GPU but after EnumAdapters I got 4 GPUs with identical information, any update on this problem???

            DX12Ptr<IDXGIAdapter> dxgiAdapter;
            for (uint32_t i = 0; DXGI_ERROR_NOT_FOUND != dxgiFactory->EnumAdapters(i, dxgiAdapter.ReleaseAndGetAddressOf()); ++i)
            {
                DX12Ptr<IDXGIAdapterX> dxgiAdapterX;
                dxgiAdapter->QueryInterface(IID_GRAPHICS_PPV_ARGS(dxgiAdapterX.GetAddressOf()));

                DXGI_ADAPTER_DESC desc;
                dxgiAdapter->GetDesc(&desc);
			}

sir yan 0 Reputation points

2024-03-21T02:20:14.9733333+00:00

Folks, there muse be some software create an adapter base on the actual graphics cards. Please check it in windows device manager

1 answer

Husnain Ali 0 Reputation points

2023-12-01T23:16:19.8733333+00:00
The issue with EnumAdapters listing the default graphics card twice is likely due to how DXGI handles GPU enumeration in some Windows 10 versions.

To work around this:

Make sure your graphics drivers and Windows are up to date.

Check for duplicates based on the unique GPU identifier (AdapterLuid).

If the problem persists, report it to Microsoft through Feedback Hub or Developer Community.

This issue may be specific to certain Windows versions, and updates could address it.
Please sign in to rate this answer.
Alden Pang 0 Reputation points

2023-12-04T20:18:35.1366667+00:00

Thanks for your answer!!

Make sure your graphics drivers and Windows are up to date.

I updated to latest driver but still have duplicate problem

Check for duplicates based on the unique GPU identifier (AdapterLuid).

Luid shows on duplicated GPU different, so if I use luid to recognize different GPUs, still have problem

If the problem persists, report it to Microsoft through Feedback Hub or Developer Community.

I guess I am doing so now...
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