PCIe 4.0 is a topic with M12 and riser cables.
I currently use a PCIe 3.0 riser cable (Asus ROG Strix Riser), which has 240 mm length. That is fine as long as I want to use View 91's vertical mount, but I've also been considering just hanging the video card inside the chassis. To be precise, I tested that with my GTX 1080 Ti, and that worked like a charm with steel threads.*
That is how it looks like:
https://www.reddit.com/r/thermaltake/comments/jb8an3/hang_it_up_when_3090_came_out_i_was_bummed_abou...Here is my question. For more freedom while hanging the video card inside the chassis, I need a longer riser cable, and those things aren't really cheap. I would like to future-proof that purchase with a PCIe 4.0 riser cable. And you may be already guessing my question: how would that work with M12E and my current PCIe 3.0 video card? Also, how will that play out when I get a PCIe 4.0 video card with a M12?
If it wouldn't work, I could also get a PCIe 3.0 riser cable. Shame that it would eventually become a bottleneck when both the mobo and the video card go PCIe 4.0.
* - Note, the steel threads are conductive, and if they snap, they could short more than one thing. Though, I couldn't snap these threads with much more force than my GTX 1080 Ti's mass produces. I was looking for carbon fiber threads but couldn't find any so far. I suppose that with a long-enough riser cable, a video card can also be hung outside the chassis to avoid the shorting-out risk (dust, noise, damage risk, space usage, and probably harder liquid cooling being the downside). I take the option to keep the video card inside the chassis.
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