AMD Confirms That Not All Ryzen 3000 Cores Are Created Equal

[Tsing]

Enthusiasts have been whining about third-generation Ryzen chips not being able to hit their advertised boost clocks, but are the complaints overblown? Maybe not, as AMD has responded to a Tom's Hardware test alluding to inconsistent core performance with a Ryzen 5 3600X.

Senior editor Paul Alcorn found that only one core in his 3600X managed to hit AMD's advertised boost frequency, with the worst core being 75 to 100 MHz slower than the fastest. The company has admitted that some cores in Ryzen 3000-series processors are indeed faster than others, a contrast from the previous generation, which could "reach boost frequencies on all cores."

We theorize the slower cores could be a contributing factor to low overclock ceilings with Ryzen 3000 processors. Ryzen 3000 series processors hit all-core overclocks 200-300MHz below the single-core boost frequency. Slower cores simply may not be able to achieve/sustain higher frequencies, thus serving as the weakest link in the chain.

 

[AntiQuark]

I've been watching this since Dan reported he could not overclock manually as high as auto. That screams avoid.
I like the fun of overclocking and dont want the experience to be worse!
And memory not running as fast as it can on Intel.
I'm not ready to jump to AMD until these are proven no longer an issue.

 

[JosiahBradley]

I've been watching this since Dan reported he could not overclock manually as high as auto. That screams avoid.
I like the fun of overclocking and dont want the experience to be worse!
And memory not running as fast as it can on Intel.
I'm not ready to jump to AMD until these are proven no longer an issue.

So because the chips perform better at stock you'll avoid them and memory speed which is proven time and time again to not affect almost any workload on the planet (even crazy server apps not being run on the desktop), you'll avoid a high performing chip series so you can get the same boring 5.1ghz on Intel chips that have no fun to overclock as they're all the same.

To each their own I guess but Ryzen 3900x dominates at almost all workloads except super high refresh gaming that was most likely compiled against an Intel chip. Feel free to spite yourself because one niche aspect is lost. Overclocking hasn't been fun since Skylake came around and basically level'd the field with their boring chips. I'm glad we actually get a challenge again with per ccx overclocks, using PBO, and tweaking the cooling system.

Overclocking's main goal was to get the maximum performance you paid for and now that comes directly out of the box, so a win in my book.

 

[AntiQuark]

So because the chips perform better at stock you'll avoid them and memory speed which is proven time and time again to not affect almost any workload on the planet (even crazy server apps not being run on the desktop), you'll avoid a high performing chip series so you can get the same boring 5.1ghz on Intel chips that have no fun to overclock as they're all the same.

To each their own I guess but Ryzen 3900x dominates at almost all workloads except super high refresh gaming that was most likely compiled against an Intel chip. Feel free to spite yourself because one niche aspect is lost. Overclocking hasn't been fun since Skylake came around and basically level'd the field with their boring chips. I'm glad we actually get a challenge again with per ccx overclocks, using PBO, and tweaking the cooling system.

Overclocking's main goal was to get the maximum performance you paid for and now that comes directly out of the box, so a win in my book.

You can try and put words in my mouth

I have no need to buy an AMD chip, it would only be out of curiosity/boredom.
If it presented a fun clocking experience and let me get the best from my ram there would be a much higher chance.
But it wont do either.

My 6700K @ 4.6GHz with 3000MHz ram at 3733MHz are great with everything I play.
As long as I get 60fps, I'm happy.
You want me to buy an AMD chip because?

 

[Dan_D]

I've been watching this since Dan reported he could not overclock manually as high as auto. That screams avoid.
I like the fun of overclocking and dont want the experience to be worse!
And memory not running as fast as it can on Intel.
I'm not ready to jump to AMD until these are proven no longer an issue.

The overclocking comes down to AMD only being able to clock the very best single core to the highest advertised boost clock speed. AMD likes to pretend there aren't single core or all core overclocking values, but there are. The established maximum boost clock value is indeed a single core value, its just that the specific core that does this varies by individual CPU. This has been the case with Ryzen in general. My Threadripper is that way. That core does 4.3GHz, the others don't. I can however do 4.3GHz on all cores.

AMD has simply corrected for its single-threaded performance by giving each CPU one binned core that can go significantly higher than the rest. The other cores are basically limited to a lower frequency such as 4.3GHz which is enough headroom to achieve their desired level of performance in multi-threaded workloads. Via PB2, this is actually closer to 4.1GHz in reality. So manual overclocking does yield positive results in specific workloads as I've demonstrated. However, the improvement is usually not worth sacrificing single threaded performance, as most use cases would benefit more from the flexibility PB2 or PBO would have with these CPU's in single and multi-threaded applications. Fortunately, you can toggle between them using Ryzen Master relatively easily.

RAM can run as fast as it can on Intel. That doesn't seem to be the issue this time around. The problem is that running it over 3733MHz or so forces the Infinity Fabric clock to a 2:1 ratio, which equates to lost performance. Theoretically, you could overcome this if you managed to clock the RAM high enough or improve latencies sufficiently. AMD even says this in its reviewer's guide.

The issue with RAM is predominantly about compatibility sucking and being able to run 4xDIMMs the way you can with Intel. Sure enough, I can take random older Corsair kits and run at all kinds of speeds on Intel motherboards regardless of whether or not I'm running in a 2 or 4 DIMM configuration. On the AMD side, speeds typically drop when you add modules like that.