Question Can a graphics card "feed back" a signal through a motherboard HDMI socket?

[PB97]

I have a slight head scratcher.

Aorus Gaming ultra motherboard
AMD Ryzen 7 2700 CPU (Visually confirmed, and confirmed by CPU-Z)
NVidia 1660TI graphics card

The CPU doesn't have on board graphics
The motherboard doesn't have on board graphics

Yet the HDMI socket on the motherboard is fully functional.

Is it being supplied from the 1660TI through the PCIE socket?

I wasn't aware that this was possible.

Purchased new from a mainstream retailer, no indication that it's a different CPU with fake markings.

 

[lvt]

Of course it's possible, even USB can transit through PCI-E.

 

[PB97]

Of course it's possible, even USB can transit through PCI-E.

So, a graphics card can send an HDMI signal through the PCI-E socket, into the motherboard, and out to the HDMI socket on the motherboard even though there is no onboard graphics capacity on the MB or CPU?

I didn't even know that this was a thing.

 

[lvt]

So, a graphics card can send an HDMI signal through the PCI-E socket, into the motherboard, and out to the HDMI socket on the motherboard even though there is no onboard graphics capacity on the MB or CPU?

I didn't even know that this was a thing.

The HDMI is just a video port, it's not restricted to a single source of video signal. In some motherboards the built-in HDMI port can be used for multi-display setup (if your GPU is compatible with that feature).

 

[hotaru.hino]

I'm confused how this is actually working. Thoughts in bullet points since I don't feel like trying to make this coherent:

• The motherboard manual, specs, or otherwise doesn't state anything about this feature.
• While PCIe can transmit any data, it's a PCIe signal, not the signal the device is actually expecting.
  • This means if a PCIe device is transmitting data that's meant to go out of a USB interface, you can't simply wire up the same lines out of the PCIe slot to a USB connector and expect the other side to use it. The data has to be converted back to a USB signal.
  • You might've seen mining rigs that use USB connectors to connect video cards over PCIe 1.0. Those things are just using USB as the physical interface, which has enough pins to support a PCIe x1 connection. Those things are not using USB signaling.
• You can't feed any arbitrary signal over the PCIe lines, because the PCIe controller doesn't know what to do with them (after all, it's only expecting PCIe)
  • If you're wondering what Thunderbolt is doing, since it can combine PCIe and DisplayPort, Thunderbolt converts both into a Thunderbolt signal. It's not some sort of combined PCIe + DP signal.
• Ryzen CPUs that aren't APUs don't have a display engine. This is necessary to generate a signal over on of the motherboard's ports.

 

[CountMike]

I have a slight head scratcher.

Aorus Gaming ultra motherboard
AMD Ryzen 7 2700 CPU (Visually confirmed, and confirmed by CPU-Z)
NVidia 1660TI graphics card

The CPU doesn't have on board graphics
The motherboard doesn't have on board graphics

Yet the HDMI socket on the motherboard is fully functional.

Is it being supplied from the 1660TI through the PCIE socket?

I wasn't aware that this was possible.

Purchased new from a mainstream retailer, no indication that it's a different CPU with fake markings.

Are you sure that it's not 2700G with Vega3 graphics ?
What is core name ?
Does HDMI out work without GPU ?