Not sure which PCIe riser to get for a second GPU in a separate case — need input

Hello everyone,

Building a dual-case AI inference setup: RTX 5090 stays in the main tower (Gigabyte X870E AORUS PRO ICE), and I want to run an RTX 5060 Ti 16GB in a separate Cooler Master Q300L enclosure about 0.5m away, connected back to the motherboard's PCIEX4\_1 slot (PCIe 4.0 x4, chipset-attached). Pure inference workload (LLM, Whisper, embeddings), no gaming.

I genuinely don't know which riser is the right pick here. The one I keep coming back to is the \*\*ADT-Link R33SH-SI-4.0\*\* (supposedly has a built-in redriver chip (no answer from seller), rated PCIe Gen4 x4), but I have no hands-on experience with it or with risers in general at this length, and I'm not sure if:

\- it's actually the right model for a \~0.5m case-to-case run at Gen4 x4, or if I should be looking at something else entirely

\- passive risers are fine at this distance and I'm overpaying for a redriver I don't need

\- there's a more proven/common model people actually use for this exact "second GPU in a separate case" setup rather than a normal in-case riser

If you've built something similar, what riser did you actually end up using, and would you buy the same one again?

Thank you so much for helping me !