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AMD Zen and Ryzen 7 Review: A Deep Dive

anandtech.com

341–350 of 359 posts

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#341

Earlier quoted context omitted.

Isn't the problem with AMD mobos that it's very difficult to find a motherboard manufacturer that supports the ECC? From what I've been reading about the upcoming Ryzen, no motherboard so far claims to support ECC.

Further down in Reddit Comments, this ASRock motherboard is linked to: http://www.asrock.com/mb/AMD/X370%20Killer%20SLIac/index.us.... Link on reddit: https://www.reddit.com/r/Amd/comments/5x4hxu/we_are_amd_crea...

Thanks! I didn't know the APU supported ECC as well.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#342

Earlier quoted context omitted.

> Because people still buy new computers and use those applications on them – that's why single-thread performance is (for the moment at least) still important. That's a load of bullshit. No one ever complained that the web is unbrowsable or an excel spreadsheet is unworkable without a high-end boutique processor. Those benchmarks are simply a load of bullshit that evaluate something that is utterly irrelevant.

Hi geezerjay, I'm trying to find a way to contact you - I was wondering whether you could comment on a previous comment about used opterons for "Budget HPC": Where would I go to find this, and build myself such a rig? Links?

You can check ebay, where they are being sold for spare change. That's where I've bought mine.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#343

Earlier quoted context omitted.

Hyperthreading is not a virtual core and as it doesn't exist as a separate core its hard for it to be idling. Bad analogies make for less than adequate understanding.

They are also called "logical cores" (I think Intel documents prefers "logical" and Sun - they invented the concept - prefers "virtual"). One logical core can appear to be idling to the OS if the parts of the physical core are in use by another (SPARC and POWER go up to 8) logical core (as it's resource starved). It seems, from the benchmarks, the AMD parts have less shared resources between logical cores (or a finer…

Pre Ryzen AMD didn't have anything like hyperthreading. The prior generation had n physical cores wherein each 2 shared a fairly significant chunk of hardware. The new generation of AMD and many generations of intel have extra hardware in each physical core that makes it look and act like additional cores. If I understand it correctly, and please correct me if I'm wrong, it mainly serves to ensure that the core is better utilized in general.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#344

I'm optimistic, but I'd like to see benchmarks for compiling code. Right now I buy really expensive 8 core cpus, because multiple threads do speed up encoding quite a bit. If Ryzen can match that at half the price, it will be much welcome.

There you go: http://www.phoronix.com/scan.php?page=article&item=ryzen-180...

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#345

Earlier quoted context omitted.

They are also called "logical cores" (I think Intel documents prefers "logical" and Sun - they invented the concept - prefers "virtual"). One logical core can appear to be idling to the OS if the parts of the physical core are in use by another (SPARC and POWER go up to 8) logical core (as it's resource starved). It seems, from the benchmarks, the AMD parts have less shared resources between logical cores (or a finer…

Pre Ryzen AMD didn't have anything like hyperthreading. The prior generation had n physical cores wherein each 2 shared a fairly significant chunk of hardware. The new generation of AMD and many generations of intel have extra hardware in each physical core that makes it look and act like additional cores. If I understand it correctly, and please correct me if I'm wrong, it mainly serves to ensure that the core is be…

You are correct.

From the benchmarks, it seems a single thread can fully utilize all resources from an Intel processor while it can't on the new AMD ones and that's why their single-thread performance is lower and their multi-thread performance is higher.

We should keep in mind the benchmarks know nothing about the new AMD parts and how to keep all parts of the processor busy.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#346

Earlier quoted context omitted.

"GCC is a useful benchmark not because it is unoptimized, but because it represents a real-world work profile that is otherwise poorly represented in SPEC." Sure, in that sense, but you also don't want benchmarks that are trivial to game by performing optimizations to them. :)

For SPEC, you can't edit the source code of the unit under test. Only the compiler and host hardware count. Some components of SPEC have been "broken" by compilers in the past, by implementing some optimization or other that suddenly made that particular test code much faster. But you don't ever get to re-write the benchmark itself, you can't replace a 2^N path with an N^3 path or anything like that. So these kinds o…

I'm aware of the limitations on SPEC editing.

However,

"If someone managed to make an optimization that could suddenly make GCC 2x faster without humans editing GCC's source, that would be a major CS breakthrough :) "

No, it really wouldn't. For example, if you optimize the line-ending and tokenization finding in GCC's parser to use SIMD, you would become significantly faster. Not 2x, but significantly. These are entirely doable by compilers. " But you don't ever get to re-write the benchmark itself, you can't replace a 2^N path with an N^3 path or anything like that."

Except, you can, by hoisting calls out of loops, etc. There are also dynamic memoization optimziations that can be applied, etc.

"If someone managed to make an optimization " This is a common fallacy that it's ever really one optimization. It's usually combinations of optimizations, each buying you N%.

I will state outright, having worked on pretty much all of the slow parts of gcc (according to spec profiles), and having a team of 80+ people working on compilers, 2x on gcc through compiler optimization is more than within the realm of possibility.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#347
post #315

Earlier quoted context omitted.

> What is interesting is the HUGE jump in multi-threaded performance on AMD. Very interesting. Indeed. Single threaded performance, however, seems bad. Virtual cores most likely share less of the actual core than on Intel parts, allowing one to compete less with the other and get more done. On my i7 laptop, on anything more demanding, I see half the "cores" idling, probably because one is using the actual underlying…

Single threaded perf isn't bad, it's just not outstanding. Many of the cases where I care about perf are cases in which the app is multithread savvy.

> Many of the cases where I care about perf are cases in which the app is multithread savvy

Yeah, as would be expected from most people on this site. Sad thing is, there's a bunch of pissed-off gamers right now who were on the hype train expecting Ryzen to be the next big thing in gaming, but it's far from it. Ryzen is great, just not amazing for gaming.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#348

Rather strange that AMD's stock is down ~ 2.5 %

A normal affect of stock price during a major announcement. It even has a name '"buy the rumor, sell the news" http://www.investopedia.com/terms/n/news-trader.asp The idea behind this, simply put, is that if you are in a trade for whatever reason with a stock that has a major announcement coming; you are pretty much at the potential peak at announcement time so it is a good time to get out.

Its not really true. Half the time it goes down half the time it goes up.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#349

Earlier quoted context omitted.

I don't know if it was attempted, but you can turn down the condescension.

Condescension is warranted towards those who assume they know anything about one's needs.

No it isn't you fuck twat.

Re: AMD Zen and Ryzen 7 Review: A Deep Dive

#350
post #10
post #4

Earlier quoted context omitted.

But it's still losing in every web and office single threaded benchmark. EDIT: compared to 7700k that costs about the same

By a pretty small margin compared to equivalent Intel CPUs from what I've seen[1]. And the ryzen chips are a whole lot cheaper and beat Intel for parallel tasks. I'm about to buy a beefy machine for FPGA development, I'm definitely considering AMD. Seems like I'd get better performance for a much lower price. I'm still waiting for more in-depth reviews though. [1] http://core0.staticworld.net/images/article/2017/03/r…

It's interesting that you'd mention that workload as it's traditionally been completely single threaded (where it matters), and exceedingly memory intensive. Do you have first hand experience with how well it scales with cores?
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