4 ms·

>NVMe You'd be limited by PCIe lanes (and memory bandwidth, 8 channel DDR5) The CPUs feature 128 PCIe lanes, compared to 7950x's 28.

by xxs 3y ago

deleted 3y ago
[deleted]
rbanffy 3y ago
If you need more than 28 PCIe lanes, then you need the big one. In any case, 28 is still a lot of IO. It makes little sense to pay for what you won't need.
- xxs 3y ago
  workstation - that would require some external GPU, so 8 or 16 lanes. 4 for chipset/USB. That leaves 8 or 16 pcie lanes for SSD, decent NVMe SSDs are 4 lanes, which means up to 4 fully enabled SSD, it's not much, esp. running RAID.
  - rbanffy 3y ago
    Not all work for workstations require a 16-lane GPU or four NVMe SSDs. Sometimes all you need is a lot of CPU cores and lots of memory at a reasonable, albeit not ludicrous, bandwidth. Although I work with 2-3 monitors all the time, I'm happy with low-end GPUs - I don't do much data visualization or 3D rendering. I mostly develop software, so I stand-up relatively thin ephemeral VMs and containers all the time. For me the core count and amount of memory is the limiting factor. To completely avoid any swapping, 64GB of RAM is needed, and more would allow me to keep a CI pipeline running all the time. If I need more space, I can spare one or two SSDs as bcache for a larger SATA array. As much as I'd love the biggest Xeon X, EPYC, AmpereOne, MI-300, or Grace Hopper under my desk, I have no need for that much power.
    - xxs 3y ago
      My initial response was to: "If you are IO-bound, why spend $3000 more on a CPU...", the desktop ones just dont have the PCIe lanes to prevent the I/O bound case. You can run 3 monitors off a iGPU (if you dont care about 3D), overall your setup is a classic desktop, running lots of VM just requires memory as the processes don't do much but exist peacefully. 128GB on a desktop CPU is totally fine with 4 DIMM slots, there won't be ECC - which DDR5 doesn't fully cover, though.

>NVMe You'd be limited by PCIe lanes (and memory bandwidth, 8 channel DDR5) The CPUs feature 128 PCIe lanes, compared to 7950x's 28.

by xxs 3y ago

>NVMe You'd be limited by PCIe lanes (and memory bandwidth, 8 channel DDR5) The CPUs feature 128 PCIe lanes, compared to 7950x's 28.

deleted 3y ago

[deleted]

rbanffy 3y ago

If you need more than 28 PCIe lanes, then you need the big one. In any case, 28 is still a lot of IO. It makes little sense to pay for what you won't need.

xxs 3y ago
workstation - that would require some external GPU, so 8 or 16 lanes. 4 for chipset/USB. That leaves 8 or 16 pcie lanes for SSD, decent NVMe SSDs are 4 lanes, which means up to 4 fully enabled SSD, it's not much, esp. running RAID.
- rbanffy 3y ago
  Not all work for workstations require a 16-lane GPU or four NVMe SSDs. Sometimes all you need is a lot of CPU cores and lots of memory at a reasonable, albeit not ludicrous, bandwidth. Although I work with 2-3 monitors all the time, I'm happy with low-end GPUs - I don't do much data visualization or 3D rendering. I mostly develop software, so I stand-up relatively thin ephemeral VMs and containers all the time. For me the core count and amount of memory is the limiting factor. To completely avoid any swapping, 64GB of RAM is needed, and more would allow me to keep a CI pipeline running all the time. If I need more space, I can spare one or two SSDs as bcache for a larger SATA array. As much as I'd love the biggest Xeon X, EPYC, AmpereOne, MI-300, or Grace Hopper under my desk, I have no need for that much power.
  - xxs 3y ago
    My initial response was to: "If you are IO-bound, why spend $3000 more on a CPU...", the desktop ones just dont have the PCIe lanes to prevent the I/O bound case. You can run 3 monitors off a iGPU (if you dont care about 3D), overall your setup is a classic desktop, running lots of VM just requires memory as the processes don't do much but exist peacefully. 128GB on a desktop CPU is totally fine with 4 DIMM slots, there won't be ECC - which DDR5 doesn't fully cover, though.