What is the most amount of NVMe SSDs that one motherboard can support? - Quora
Answer (1 of 2): On just the motherboard? Well, there is a $1,000 motherboard for AMD Threadripper with 5 M.2 slots. The ASUS ROG Zenith II Extreme Alpha.
It's got 4 PCIe slots, and I think you could use an NVMe in three of those, with one for a GPU.
So I think eight woukd be about the max. May...
Biostar TB360-BTC D+ (Intel 8th and 9th Gen) LGA1151 ...
Asus reveals AMD B850 motherboard with custom 600W GPU slot and concealed connectors.
PC Case Sizes: E-ATX, ATX, mATX, and ITX Compared | GPCB
Mid Tower PC case, Includes 4 x 120mm Umbra Void fans, Up to an E-ATX motherboard, 7 + 3 expansion slots, Tempered glass side panel, Up to 380mm long GPU.
What are Small PCIe x1 Slots Used For? - CGDirector
We recommend a minimum of 8 PCIe Gen 4 lanes per physical x16 slot on the motherboard for a four-GPU build. You may use fewer GPUs and populate the empty PCIe slots with storage or network cards, depending on your requirements.