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by gigatexal 3392 days ago
yes but four modules of ryzen to make this beastly naples chip isn't going to be clocked at the same frequencies. the top end intel chips have TDPs of 165W but 4 ryzen chips at 3.6ghz have a tdp of 65w a piece and you're not going to see a 260W server chip if you want to sell into the datacenter.
5 comments

The Ryzen 7 1800X has a TDP of 95W and beats the 140W Intel i7-6900K by 4% in performance. They've made some huge jumps in power efficiency.

I don't know if AMD will make a new architecture or not, but I can't see why they wouldn't just release 32 Ryzen cores side-by-side and underclocked at the stock configuration.

The 1800X will use 130W+ in the same scenarios as the 6900k. AMD just seems to be defining TDP differently.
The thermal design power is the maximum amount of heat generated by a computer chip or component that the cooling system in a computer is designed to dissipate in typical operation. TDP =/= power consumed
> TDP =/= power consumed

Where do you think the heat comes from? Or where do you think the power that doesn't turn into heat goes?

I think he is trying to argue that TDP is a figure about the cooling requirement during peak power usage. Actual power usage may or may not be less during typical workload.
As far as TDP goes, the transferrence of electrical energy to heat is equivalent to that of a space heater as Puget Systems demonstrated here: https://www.pugetsystems.com/labs/articles/Gaming-PC-vs-Spac...
but TDP is also a function of power consumption, directly proportional. So comparing TDP of processors of similar fabrication should tell you about comparative power consumption if not the exact difference.
I've seen benchmarks showing the 95w number is very unrealistic and that it actually uses more like the Intel processor under certain loads
Wow, that's pretty insane. Underclocked to 3.3Ghz it runs at ~42 watts and is benching at ~178.5% performance per watt vs stock clock. This CPU will be very interesting to see in the datacenter space.
They will likely drop the clock. I don't think the market cares at all about how much a CPU takes. If a 1U box has competitive performance AND better performance/watt then it's attractive. It if has worse performance/watt than it's not.

AMD might well steal some of the dual socket market with a dual socket, and maybe some of the quad socket market with dual sockets.

Considering that the current ryzen at $500 is relatively competitive with the $1,000 intel (basically a relabled Xeon with 4 memory busses in the LGA2011 server socket) a quad module (32 core/64 thread) in a socket sounds pretty good. Even if it's more watts than the intel.

The E7's go to 160W each. If you can drive better than 1.7x the performance and stay within the maximum thermal output per physical volume, I see no reason why not to use this.

One reason, perhaps, is if my binaries are compiled with Intel-specific optimizations and it's inconvenient to deploy separate AMD-optimized binaries.

I can see a use case for it, as long as it delivers on performance. No one minds high TDP, as long as it offers a performance advantage. Hell, some servers have 4-8 Titans in them, and no one is complaining about their TDP. If a 260W CPU TDP is justified by the performance, no one will care.
The bigger E7 scratch the 200 W mark pretty hard and IBM already had POWER chips go beyond 200 W. However, cooling and power density are ... problematic. The same goes for accelerators. Supermicro will happily deliver you a 1U box with four pascals and two Xeon sockets, but there is no datacenter in the world were you can stuff 42 of those in a cabinet. [Which doesn't mean that these don't make sense]

However, high end systems don't lend themselves well to mass-deployment (i.e. scale out).

maybe for single server or academia setups, but in datacenters TDP and power consumption absolutely do matter.
And that was my point as well.
I'm more than willing to admit I could be wrong. And maybe Intel will push the TDP envelope with servers as well if Naples proves a threat when things all shake out. Just if Intel hasn't put a ~250W server chip into production I doubt AMD will then again if it performs that much better then there's a calculus there that will need to be done. My prediction, based on no evidence, is that this 32-core chip will be clocked at 2.6ghz and boost to 3.2. Shot in the dark, but given current TDPs that's where I think things might shake out to.