Saturday, 30 May 2020

AMD Ryzen 5 3600 review (4.2 stars)

Overview

6 cores, 12 threads
One 8 core chiplet (2x 4core CCX; 1 core disabled in each CCX)
Base clock 3.6Ghz Boost up to 4.2Ghz
65W TDP
Core fab: 7nm
SoC (I/O) fab: 12nm

While the processor does deliver on performance for the most part, hype around it is real and unjustified to an extent. Let's have a look why.

The temperature spikes on 7nm silicon are unbelievable because of the increased transistor density. Within 1 or 2 seconds the temps reach 65 -70 degrees C from 30-40C (at idle). This, unless you manually set the volts, thereafter the spike gets linear.

    At stock settings, Precision Boost Overdrive (Intel's Turbo Boost equivalent) works fine to overclock the system but instantly falls flat as soon as the chip reaches 70-80 Deg C range. The voltage it uses goes up to 1.4v in sudden bursts taking the clocks up to advertised boost speeds (for a mere second or two) and then back to 3.9Ghz (or even lower depending on your cooling and case)  at sustained loads because the heat is tremendous. The volts stay quite high, but the chip lowers the clocks to keep the thermals in check. Eg. I can manually put the clocks @4100Mhz all cores at 1.29v but PBO will keep the clocks @3966Mhz at the same voltage. Which really just shows that it does not take silicon lottery into account and starts with a higher base voltage to keep the chip stable but that causes excessive heating too!

    The cooler that ships with the chip is fine definitely better than Intel ones but not if you want to extract 100% performance out of the Ryzen. It's good for dissipating around 60W, but the package (CPU+SoC+Cache) can go up to 90w so there it gets stretched thin.

    To sustain the higher clocks on higher workloads at safe temperatures, an after-market cooler will have to be used at all costs. Overclocking headroom is negligible as a result. You will have to manually feed in the Clocks and Voltage. Your best bet is to stay near 1.25v and use the highest clock that your chip is stable at which should be around 4.0Ghz but beware of heat at sustained workloads. These new AMD chips are not as stable as Intel at such high temps (90C) because of the 7nm process. It's better to not go above 80C. And at least 10C gap is advisable for longevity as the max temp mentioned by AMD is 95C.

As you can see the chiplet is on the far side of the die,
which results in uneven heating of the IHS
and sub-optimal cooling.

Image courtsey: wccftech.com



(The safe range for 7nm is around 1.25v or at max 1.3v if you wanna YOLO. Initial 7nm chip batches needed higher V to get to higher clocks, but as the fabrication process has matured since the production started, new chips can do the same at lower volts.

Not being able to achieve higher clocks can be party contributed to the new smaller node. While Intel is still optimising the 14nm process, they are able to get higher clocks along with binning. AMD's Ryzen chips below the Ryzen 9 are low binned models, hence higher clocks are further reduced. Best binned chips are reserved for the Epyc server SKUs.)


Another thing is RAM timing, which will have a huge impact on your system responsiveness and gaming. Get the highest quality RAM chip that you can afford. Nothing less than 3200Mhz CL16. The stock latency on Ryzen 3600 is a lot because of the delay in how the two CCXs communicate with each other. Intra core latency within the CCX is very impressive however, but the OS does not necessarily feed the instructions to cores in their particular order to take advantage of it. Here is how it works: suppose one core from CCX0 wants to exchange data with another core in CCX1, the data will have to pass through the infinity fabric to the I/O SoC and then back, instead of a direct communication. So, you need your RAM to compensate. In workstation environments, this is not a major issue but for high fps gaming it certainly is.

Concluding thoughts and the competition

    The Zen architecture that came in 2017 had made the x86 chips competitive again in terms of IPC (instructions per cycle). AMD themselves have improved to more than 52% as compared to IPC on their Excavator design. Zen 2 leads that forward again with optimisations to Zen/Zen+. This is a seriously impressive feat, and a good thing for consumers and industry alike. Intel's lack of effort had made x86 architecture stagnant and consumers were getting restless with the ever high prices. As it stands currently, AMD leads in the IPC and core count department and Intel leads in the clocks and single threaded performance. Based on this the final purchase decision should be made.

The multi-core performance on the Ryzen 3600 is great and beats the competition in every way, both cost and result wise. This is in fact Ryzen's biggest strength, massive amounts of work threads are completed with ease at a very approachable price point.

Test Scores

My current tune (safe upper limit voltages in brackets):

All cores @3925Mhz 1.18v (1.25v)
SoC @1.0v (1.1v)
Infinity Fabric Clock 1667Mhz
Memory Controller Clock 1667Mhz
3200Mhz CL16 RAM @ 3333Mhz CL16 1.34v (1.37v)

Scores based on the above tune
AGESA 1.0.0.4
Cinebench R15 multi core : 1566
Cinebench R20 multi core : 3533

AIDA64 (stress FPU) Temp - 82Deg C (32Degree C ambient)
AIDA64 Latency Test - 74.2ns

AGESA 1.0.0.3
Cinebench R15 multi core @stock with PBO (18Degree C ambient) : 1577
Cinebench R15 multi core @3950Mhz 1.165v (18Degree C ambient) : 1585
Based on the above two scores you can see how PBO throttles the clocks even at lower ambient temperatures which drastically lowers the score. Running Cinebench r20 @stock with PBO takes the temperatures to 88C (32C ambient) with starting freq @3950Mhz and @3800 by the end of the run because of extensive throttling with an abysmal resulting score of 3490, of course. So you see it's a huge waste of potential and only works for light loads like general desktop computing. The moment chip reaches 70C, boost clocks drop fast.

My silicon lottery level in case you're wondering, all cores @4100Mhz 1.29v Stable; no LLC

You will get way better results using an aftermarket cooler, this is definitely not the best case scenario. If you're getting this chip for tuning/OC please get a motherboard that supports LLC (line load calibration). The Vdrooop is real when all 6 cores start churning out data.

    In my conclusion, I would say yes this chip is very good, but it is highly dependent on the user and how much time he/she is willing to put into tuning it correctly. Because the difference can be night and day. For casual gamers, the Ryzen 3500 is a better bet and then using the saved money for a better GPU and RAM. For mixed usage between productivity/gaming the 3600 delivers. Just get a good CPU cooler else you'll be frying this chip with the stock one.


FINAL SCORES
Gaming Score - 4*
Productivity Score - 5*
Value for Money - 5*
Overclock ability - 3*
Stock Cooler - 3.5*
Stock Performance - 4*
Tuned Performance - 5*

Additional observations: Based on my testing I have seen that if you could keep the chip cool, say below 75C, you can get away with slightly lower voltages as well (around 50-100mV less). The chip needs higher voltages at higher temperatures. I cannot say this for sure though, if you have some idea, please leave me a comment.

Thank you for reading.


Tl;dr
Get an aftermarket cooler
Get a fast RAM and tune it
Set your volts and clocks manually

Recommended for
CPU Intensive Gaming: Yes, higher thread count helps
Casual Gaming: No, get the R5 3500 instead
High FPS Gaming: No, go with i7 8700K or i5 10600K
Productivity: Big YES

Have more money? Go with R7 3700x, it comes with a better cooler and moar coars
Or buy a decent motherboard and a CPU cooler and OC the heck out of this chip.