Rome in Detail: A Closer Look at AMD's 64-Core 7nm EPYC CPUs

milkod2001

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Just wondering if with PCIe 4.0 will be also get faster m2. SSD drives or it will be the same. Also what other real benefits are coming from PCIe 4.0?
 

bit_user

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I don't want equal latency to come at the expense of low latency. The current EPYC architecture provides low latency for local memory accesses, which can be achieved though NUMA-aware apps, OS, and/or VM partitioning.

I hope AMD didn't just cede ground on one of EPYC's strengths.
 

bit_user

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The main benefit for consumers (and we still don't know when it will arrive in a consumer platform) will be that you can do more with fewer PCIe lanes. So, splitting your GPU lanes to dual x8 will be virtually painless, as will splitting your M.2 to dual x2 connections.

Personally, I'm most interested in seeing full-rate 10 Gbps ethernet on a little PCIe 4.0 x1 card.


Yes, they have exceeded what PCIe 2.0 can support, as that's < 2 GB/sec for a x4 link (or a x2 link @ PCIe 3.0).
 

stdragon

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I can imagine the TDP being at least 200 watts under full load. But how much more than that?? I mean, I get 7nm is more efficient than 14nm at the transistor level, but there's also a lot more dies on that package too. Will be very interesting on cooling strategies for a racked up server that uses as few U's as possible.
 

gasaraki

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OK, so from this article, you say that the Rome processor will have Zen 2 "chiplets" and PCIe 4.0 lanes. So you are saying that Zen 2 will contain PCIe 4.0 lanes unless the PCIe 4.0 lanes have been moved out on to the I/O processor. If that's the case then the chiplets have to talk to the IO processor via Infinity Fabric 2.0 then to the PCI bus. Seems like that would increase latency.
 

hannibal

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That us the general consessus. There is more latency but separate IO can feed separate cpus more evenly. So you win something and lose something. Intersting to see bencmarks! They did not change the system for no reason!
 

adrianxw

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I'm wondering about the cooling of these beasts. That is a lot of cores and threads, if you run BOINC or another platform like that, all cores and threads are in use pretty much all the time. Clock speed is not mentioned.