3 ms·
> Unless you are using multiple GPUs or another PCI device You mean like having a GPU and one or more PCIE NVMe storage-devices?
by josteink 9y ago
> Unless you are using multiple GPUs or another PCI device
You mean like having a GPU and one or more PCIE NVMe storage-devices?
- jacquesm 9y agoNo, as in 4 GPUS and/or one or more PCIE NVMe storage devices or PCI based comms cards such as infiniband cards.
- cbetz 9y agoThis. I've been trying to put together a small home lab xeon e3 system that can theoretically support nvme+gpu+infiniband. It's tough. Typically you get something like 3 full length PCIe slotson a xeon e3 board (c236 chipset). BUT they can't all run full speed at 16x (16/16/16). You have to then choose between 16/8/8 and 16/16/0 due to the lack of PCI lanes.
- powercf 9y agoCan you explain why you need 16/16/16? Wikipedia tells me that one x16 PCIe 4.0 connection has a capacity of 32GB/sec (x8 is 16GB/sec). A quick search shows NVMe drives with a sustained read or write speed of ~2-4 GB/sec. Equally for the GPU - you need to move a lot of data in/out of the GPU to saturate a x8 connection.
- jacquesm 9y agoIt's rare to run that sustained, usually it's bursty so the extra bandwidth is very much needed.