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Kinda excited and can't wait for more details. Key detail from anandtech article: "Threadripper this is still the case: the two now ‘active’ parts of the chip

Kinda excited and can't wait for more details. Key detail from anandtech article: "Threadripper this is still the case: the two now ‘active’ parts of the chip do not have direct memory access. This technically adds latency to the platform, however AMD is of the impression that for all but the most memory bound tasks, this should not be an issue"

sliken 8y ago
Sounds pretty much exactly like an Epyc, but with half the memory channels disabled. Seems kinda silly unless it's pretty cheap. After all the 7351P is $750, guarantees ECC, and has twice the memory bandwidth of the threadripper.
- loeg 8y ago
  7351P is the 16-core Epyc part. The comparable Epyc part is the 32-core 7551P, at $2317 (Newegg). There is definitely differentiation between the server line of chips and the TR "HEDT" chips, other than the crippled memory channels. The TR4 socket sacrifices half of the SP3 memory channels to use for more power. As a result, TR models come with (much) higher stock clocks: 3.0 GHz base -> 3.4 GHz all-core turbo vs Epyc 7551P 2.0 GHz base -> 2.55 GHz all core. So all in all, TR may be better for your workflow than Epyc even at the same core count and price (if clock matters more to you than memory bandwidth). And keep in mind, server boards aren't free.
  - sliken 8y ago
    Not sure I get the value. Unless you like motherboards with LEDs hot glued everywhere. To compare: Epyc 7351P, 2.9GHz, 16 core, 32 threads, 8 memory channels = $799 TR 1920X, 3.5GHz, 12 core, 24 threads, 4 memory channel = $761 TR 1950X, 3.4GHz, 16 core, 32 threads, 4 memory channel = $959 Sure the 1950X is 17% faster clocked, but with half the mem bandwidth and half the mem channels (half the performance for random lookups). So generally the 1950X will be 17% faster with no cache misses, and 50% as fast with all cache misses. Motherboard prices are pretty close, the Epyc, Dual GigE, 3x PCI-e x16, etc = $369. I found some TR boards cheaper, but not with ECC or 3x PCI-e x16. Sure the future thread ripper 2 will be faster... but so will the Epyc 2. Not sure I see the point in the TR.
    - deno 8y ago
      The 17% faster clock is the point. No one wants their computer to be 17% slower because sometimes they also want a lot of threads. In server terms it’s sort of like latency vs throughput.
    - loeg 8y ago
      > Not sure I get the value. Unless you like motherboards with LEDs hot glued everywhere. Clock and single core performance absolutely matters to some customers. This is part of why Intel can continue to dominate the home and server market despite selling lower core count chips — they are clocked a little higher and have a little higher IPC. (Also, I totally agree about the silly LEDs, but I also think board manufacturers wouldn't do it unless it produced a return, i.e., added value on average.) > To compare: Epyc 7351P, 2.9GHz, 16 core, 32 threads, 8 memory channels = $799 > TR 1950X, 3.4GHz, 16 core, 32 threads, 4 memory channel = $959 7351P @2.9 GHz is the boost clock — base is 2.4. 1950x @3.4 is the base clock — boost is 4.0, on up to 4 cores (not all-core like the 7351P part). > So generally the 1950X will be 17% faster with no cache misses, and 50% as fast with all cache misses. Your 17% number is sort of wrong, or missing the point — yes, that's the clock difference for all-core workloads, but TR boost kicks in at 1-4 thread workloads. 4.0/2.9 is huge. That's 38% additional CPU on (very common) 1-4 thread workflows. That's worth a premium to some people. The obvious question you might then ask me is, if your workflow is only 1-4 threads, why buy a 16 core CPU? Well, sometimes people have workflows that vary over time. Maybe some of the time you only need a few cores to manage interrupt traffic and keep the GPUs fed, and maybe other times you do want all of the cores to complete a parallelizable, CPU-bound task like compilation or h.265 compression faster. If your workload is exclusively embarassingly parallel and you can keep all cores busy all the time, yes, a server platform like Epyc 7351P is a much better value for you than TR. Or if your workflow needs more than 80 GiB/s (TR1) or 95 GiB/s (TR2) memory throughput, a server platform like Epyc is probably a better value for you. > Sure the future thread ripper 2 will be faster... but so will the Epyc 2. Not sure I see the point in the TR. Epyc 2 will almost certainly not be clocked higher than TR2, due to the additional power draw the TR socket has vs SP3 — though, the gap may shrink.
      - sliken 8y ago
- paulmd 8y ago
  AMD is going to be pushing Epyc to 64 core with the new 7nm node early next year, they just pushed the changes to the TR lineup first.

sliken 8y ago

Sounds pretty much exactly like an Epyc, but with half the memory channels disabled. Seems kinda silly unless it's pretty cheap. After all the 7351P is $750, guarantees ECC, and has twice the memory bandwidth of the threadripper.

loeg 8y ago
7351P is the 16-core Epyc part. The comparable Epyc part is the 32-core 7551P, at $2317 (Newegg). There is definitely differentiation between the server line of chips and the TR "HEDT" chips, other than the crippled memory channels. The TR4 socket sacrifices half of the SP3 memory channels to use for more power. As a result, TR models come with (much) higher stock clocks: 3.0 GHz base -> 3.4 GHz all-core turbo vs Epyc 7551P 2.0 GHz base -> 2.55 GHz all core. So all in all, TR may be better for your workflow than Epyc even at the same core count and price (if clock matters more to you than memory bandwidth). And keep in mind, server boards aren't free.
- sliken 8y ago
  Not sure I get the value. Unless you like motherboards with LEDs hot glued everywhere. To compare: Epyc 7351P, 2.9GHz, 16 core, 32 threads, 8 memory channels = $799 TR 1920X, 3.5GHz, 12 core, 24 threads, 4 memory channel = $761 TR 1950X, 3.4GHz, 16 core, 32 threads, 4 memory channel = $959 Sure the 1950X is 17% faster clocked, but with half the mem bandwidth and half the mem channels (half the performance for random lookups). So generally the 1950X will be 17% faster with no cache misses, and 50% as fast with all cache misses. Motherboard prices are pretty close, the Epyc, Dual GigE, 3x PCI-e x16, etc = $369. I found some TR boards cheaper, but not with ECC or 3x PCI-e x16. Sure the future thread ripper 2 will be faster... but so will the Epyc 2. Not sure I see the point in the TR.
  - deno 8y ago
    The 17% faster clock is the point. No one wants their computer to be 17% slower because sometimes they also want a lot of threads. In server terms it’s sort of like latency vs throughput.
  - loeg 8y ago
    > Not sure I get the value. Unless you like motherboards with LEDs hot glued everywhere. Clock and single core performance absolutely matters to some customers. This is part of why Intel can continue to dominate the home and server market despite selling lower core count chips — they are clocked a little higher and have a little higher IPC. (Also, I totally agree about the silly LEDs, but I also think board manufacturers wouldn't do it unless it produced a return, i.e., added value on average.) > To compare: Epyc 7351P, 2.9GHz, 16 core, 32 threads, 8 memory channels = $799 > TR 1950X, 3.4GHz, 16 core, 32 threads, 4 memory channel = $959 7351P @2.9 GHz is the boost clock — base is 2.4. 1950x @3.4 is the base clock — boost is 4.0, on up to 4 cores (not all-core like the 7351P part). > So generally the 1950X will be 17% faster with no cache misses, and 50% as fast with all cache misses. Your 17% number is sort of wrong, or missing the point — yes, that's the clock difference for all-core workloads, but TR boost kicks in at 1-4 thread workloads. 4.0/2.9 is huge. That's 38% additional CPU on (very common) 1-4 thread workflows. That's worth a premium to some people. The obvious question you might then ask me is, if your workflow is only 1-4 threads, why buy a 16 core CPU? Well, sometimes people have workflows that vary over time. Maybe some of the time you only need a few cores to manage interrupt traffic and keep the GPUs fed, and maybe other times you do want all of the cores to complete a parallelizable, CPU-bound task like compilation or h.265 compression faster. If your workload is exclusively embarassingly parallel and you can keep all cores busy all the time, yes, a server platform like Epyc 7351P is a much better value for you than TR. Or if your workflow needs more than 80 GiB/s (TR1) or 95 GiB/s (TR2) memory throughput, a server platform like Epyc is probably a better value for you. > Sure the future thread ripper 2 will be faster... but so will the Epyc 2. Not sure I see the point in the TR. Epyc 2 will almost certainly not be clocked higher than TR2, due to the additional power draw the TR socket has vs SP3 — though, the gap may shrink.
    - sliken 8y ago
paulmd 8y ago
AMD is going to be pushing Epyc to 64 core with the new 7nm node early next year, they just pushed the changes to the TR lineup first.