✧✦Catherine✦✧please enjoy this piece of modern art i've just constructed
it's held together with sticky tape not just because it's thematically appropriate but also because i've lost the screws that came with it. or maybe the screws were never in the box in the first place. i'm not sure
Tobias@whitequark I tried a simliar thing, but turns out my (elderly) motherboard doesn't do bifurcation. So I had to buy the expensive card: https://www.sonnettech.com/product/m2-2x4-ssd-low-profile-pcie-card/overview.html
Cause it has its own PCIe switch.
@krono this is not a new motherboard, it runs on lga2011v3. it just has a good (chinese) bios. from... this year actually
@whitequark Oh, my is around one generation newer (lga1151), but a generic AMI BIOS on an Asus "Gaming" board (Z170I) that came with the case.
I hadn't had high hopes to begin with; no new bios since 2018.
I just learned that the bios has a lot say in bifurcation…
@krono in practice i think it's mostly a bios thing. i think it's not actually very easy (if possible at all?) to lay out an X16 PCIe slot that cannot be split, but this is based on a distant memory of reading about the Intel FlexIO thing
elly@whitequark @krono You can bifurcate PCIe on desktop systems by changing lane assignment in IFD (AFAIK), but that only affects PCIe lanes hanging off of PCH (Chipset).
If you have a mobile SoC that has all lanes on SoC (like Intel N100) you can bifurficate all you want, same goes for AMD.
If you have a mobile SoC that has all lanes on SoC (like Intel N100) you can bifurficate all you want, same goes for AMD.
AMS@elly @whitequark @krono So you'd think someone would make a way to get all 24 lanes to slots from an AM5 as 16x and 8x instead of dumping a bunch into m.2. (I can boot off of some NVMe hanging off the chipset, then use my big NIC after that)
@AMS @whitequark @krono Not sure how AM5 is done, but I'm currently working on adding support for Zen 4 (Ryzen 7000 Mobile) to coreboot, using my work laptop (Framework 16) as a test platform and it looks like you can indeed assign lanes however you want on AMD:
https://review.coreboot.org/c/coreboot/+/89634/17/src/mainboard/framework/lotus/devicetree.cb#27
I'm pretty sure I can split that GPU bay (8 lanes by default) into 2x4, 4x2 or maybe even possibly 8x1. This is just a speculation though because I've been refused access to AMD's documentation, so I'm basically RE-ing the crap out of it.
https://review.coreboot.org/c/coreboot/+/89634/17/src/mainboard/framework/lotus/devicetree.cb#27
I'm pretty sure I can split that GPU bay (8 lanes by default) into 2x4, 4x2 or maybe even possibly 8x1. This is just a speculation though because I've been refused access to AMD's documentation, so I'm basically RE-ing the crap out of it.