Question:

How can I connect a LG Ultragear 5K monitor with Thunderbolt input to a PC with an AMD 5800X CPU and a NVIDIA 3080 Ti GPU without changing the motherboard?

I have a PC with an AMD 5800X CPU and a NVIDIA 3080 Ti GPU, which do not support Thunderbolt output. I want to use a LG Ultragear 5K monitor with Thunderbolt input as a secondary display. Is there any adapter that can convert DisplayPort or HDMI output from the GPU to Thunderbolt input for the monitor, without requiring me to upgrade the motherboard or the CPU?

Answer:

One possible option is the [StarTech.com Thunderbolt 3 to Dual DisplayPort Adapter], which can connect to your GPU via a USB-C to DisplayPort cable, and then output two DisplayPort signals that can be combined by your monitor to create a 5K resolution. However, this adapter costs around $200 and may not support the full 60Hz refresh rate of your monitor. Another possible option is the [Sonnet Thunderbolt 3 to Dual HDMI 2.0 Adapter], which can connect to your GPU via a USB-C to HDMI cable, and then output two HDMI signals that can be combined by your monitor to create a 5K resolution. However, this adapter also costs around $200 and may not support the full 60Hz refresh rate of your monitor.

A cheaper and simpler solution is to use a [USB-C to DisplayPort 1.4 Cable], such as the [Cable Matters 32.4Gbps USB C to DisplayPort 1.4 Cable], which can connect your GPU to your monitor directly, without any adapter. However, this solution will not use the Thunderbolt input of your monitor, but the DisplayPort input instead. This means that you will not be able to use the Thunderbolt features of your monitor, such as daisy-chaining, power delivery, or data transfer. You will also need to use a separate cable for audio, as DisplayPort does not carry audio signals. However, this solution will support the full 5K resolution and 60Hz refresh rate of your monitor, and will cost less than $20.

In conclusion, there is no perfect solution to connect a LG Ultragear 5K monitor with Thunderbolt input to a PC with an AMD 5800X CPU and a NVIDIA 3080 Ti GPU without changing the motherboard. You will have to compromise on either the cost, the performance, or the functionality of your setup. The best option depends on your budget and your preferences.