The fact is that the PCIe lanes are rarely saturated so this is why PCs don't need as many lanes as you posit. Lanes can be shared. To benchmark this load may have you searching for tools I have never looked for since I've rarely run into possible PCIe bottlenecks,
More common is that a gamer builds a PC but opts for a single stick or RAM. In today's PCs most have dual channel RAM which if they setup as single does create a bottleneck for both CPU and GPU.
I've read that CPUs have PCIe lanes and that those are used by the graphics card.
1.- So if a processor has 20 PCIe lanes, does that mean I can only have one x16 (or 2 x
graphics card?
2.- Does that mean if I want two x16 I need a 40 PCIe lanes processor?
3.- If that's the case, why does having multiple graphics cards on a 20 PCIe lane processor actually makes a difference while GPU rendering?
(About the third question, here's a post showcasing it)
https://www.cgdirector.com/best-har...-redshift-vray/
4.- If it doesn't affect negatively having multiple graphics cards on a 20 PCIe lane processor while doing GPU rendering, then, when does it actually matter? (negatively)
Thank you

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