Can anyone shine any light on these extension cables? I want to bring out the rear IO type C port to somewhere easily accessible. I'm getting some strange results with 2 extension cables I've bought. I've got a NVMe to USB 3.2 gen 2 10 Gbps caddy, with a short ~15cm cable. Without extension: expected 1000 MB/s on both Ryzen 3600 CPU port and RTX 2080 Ti USB-C port. With extension A (some cheap generic, 50cm): on CPU port, drive seems to have connectivity issue, goes offline when accessed. Didn't test GPU port. With extension B (50cm silver 10Gbps UGreen): 250 MB/s on CPU, 450 MB/s on GPU. Retest without extension: same 1000 MB/s on GPU. Top, GPU port. Bottom, retest on GPU port. Are these extension cables doomed to failure? But what might be the reason for difference in speed on different ports?