I'm wondering if it's feasible to take a PCIe x16 slot and break it down into sixteen x1 slots. I know some motherboards support bifurcation into 4x4 configurations, but I'm curious about using a PCIe bifurcation card to extend that further. Can I use two of these cards in tandem to achieve a 16x1 setup? Are there chipset limitations that would prevent this? And even if I could, would the motherboard be able to detect and work with this kind of configuration? It might sound extreme since who really needs 16 graphics cards, but I'm just looking for clarity on whether this setup is realistic.
6 Answers
Sure, you can try, but I wouldn't recommend taking it to extremes. PCIe slots can get pretty complex when you start daisy-chaining them like that. Plus, both your BIOS and hardware need to be on board with all that bifurcation, and it can get finicky real quick.
The connections from the CPU usually group into sets of x4, so it’s relatively straightforward for that format, but direct x1 splitting isn’t practical. You could theoretically find some expensive switch that might allow that, but it’s just not something that anyone would want to manufacture since x4 is the standard range people deal with.
While it is technically possible, I've never really seen a working example of this kind of setup. However, you might want to check out the HighPoint Rocket cards. They have options for PCIe switching that could theoretically let you achieve a similar outcome without needing those x1 slots. It's definitely on the pricier side though!
I think people once did this for mining rigs where lots of x1 slots were needed. Some motherboards even support a ton of GPUs. Check this out for some inspiration: https://www.pcgamer.com/asus-has-a-motherboard-that-supports-up-to-19-gpus/
In theory, yes, splitting it could work. But honestly, I don't think consumer boards support that level of bifurcation. You're likely to run into some hefty limitations.
Short answer? Not really. The boards that have bifurcation chips focus specifically on dividing x16 into x4 and don't support splitting down to x1.
Even with server hardware, you might get x2 lanes working, but I haven't seen anything functioning with x1.