Storage Custom B550 build - PCI-e 4.0 SSD alongside PCI-e 3.0 riser cable for graphics?

DrDev

Case Bender
Original poster
New User
Oct 12, 2020
2
1
Hi. I have been a follower of SFF.network for a number of years, and have been inspired to build (another) custom ITX build. I have a very specific query re: B550 chipset and use of PCI-e 4.0 SSDs when you have to restrict the PCI-e mode for the Graphics card to Gen 3.0. As is often the case, I use a (30cm) PCI-e riser cable for my build, but it's only Gen 3.0. Leaving my Gigabyte B550i motherboard in "auto" mode for graphics PCI-e results in significant instability (I'm lucky to get the PC to boot 5% of the time). So, does the fact that I have set PCI-e to Gen 3.0 for the graphics card mean that I can't use a PCI-e Gen 4.0 m.2 SSD (such as a Samsung 980 pro) and still achieve the benefits of a PCI-e 4.0? If so, is my only option to upgrade the PCI-e riser (as I'm loathe to spend >£70 on a cable!) or are there other options?
 

DrDev

Case Bender
Original poster
New User
Oct 12, 2020
2
1
Take a look at this post, it looks like the NVMe speed is affected by your PCIe speed.
Thanks for that - that's what I thought. Looks like I'll have to stick with a PCI-e 3 SSD for the moment. Hopefully this will drive the availability of ..er.. better value PCI-e 4.0 riser cables!
 
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PVC

Cable-Tie Ninja
Jul 12, 2020
177
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Take a look at this post, it looks like the NVMe speed is affected by your PCIe speed.
And while you are at it (see this post too), because I was thinking that I could do an APU-build/No-GPU and use two PCIe 4.0/Gen4 NVMe sticks (or at least one PCIe 4.0/Gen4 NVMe stick). I thought this might work since there was no GPU card installed to be in conflict for PCIe lanes?

Well NO. PCIe 4.0/Gen4 won't work even for an APU build because the Renoir desktop APUs don't support PCIe4.0/Gen4, period.