Understanding Ryzen (Zen 2) Behavior and Performance

[Illusion of Progress]

I was reading another post and went to make a reply, but I didn't want to hijack another person's thread so I'm making this one (for reference, that post was here and I'm hoping Escorve and xSOSxHawkens can weigh in here). Apologies for the somewhat broad title, but I'm trying to better understand the behavior and performance of my CPU, because I'm a bit lost by some of it.

For background, I'm not new to PCs or overclocking. I had myself pretty well familiar with overclocking Pentium 4/Cores 2 Duo and my prior Core i5 (Sandy Bridge), but I am new to Ryzen.

I'm a recently new owner of a Ryzen 7 3700X. I haven't done anything with it (only notable mentions are D.O.C.P. is set and Infinity Fabric clock is running 1,800 MHz). I'm still on the stock heatsink and fan (yes, I plan to upgrade) and I don't fully understand everything yet, so until I do, I figured there was little sense messing with trying to set anything. So my Ryzen 7 3700X sits at default/auto for now.

It seems difficult to understand which voltages and temperatures are actually right, let alone which is safe. My 32nm Sandy Bridge was sitting at ~1.26 or 1.28V for 4 GHz for a decade and now people are saying 1.4V, which I remember being the infamous danger zone for those CPUs, is suddenly fine for a 7nm Ryzen? To be honest I don't even think I was giving my 45nm Core 2 Duo that much. I do see my Ryzen reporting 1.4V to even 1.5V but I understand voltage of danger correlates with temperature, so I'm not sure if this is acceptable under idle or for transient times. I have no idea. I know LLC was told to be taken with caution specifically to avoid transient spikes. It's like having to unlearn things. It's hard to find out what is what, and I can't seem to find temperature results for the cores (all I can find is the generic CPU temperature, or is this all there is/the one that matters now?).

I understand in basic terms how boosting works (also a new thing), and how modern CPUs are clocked much higher to their ceilings than CPUs of years gone by. So this means unless you can get an all core boost near what the single core boost reaches, it seems you have a tough decision to make too.

So here's the observed behavior of my CPU.

It boosts to basically the advertised "up to 4.4 GHz" during lesser core count loads, but I fear I'm missing out a lot on higher core count loads. Cinebench R20 gives me a score of ~4118, and from what I'm finding, this is very low for my CPU, which should be closer to the 4750 or 4850 range or so. I noticed all the cores sit at ~3.443 GHz during Cinebench too which is below base clock speed of 3.6 GHz; I didn't know it'd ever go below. In other loads, it seems to settle ~3.7 GHz. My single core results seem in line; it boosts to 4.392 GHz and I get a score of 501 which is exactly normal. In CPU-Z, my single-score results are slightly better than par, but again seem lower in all core tests.

https://i.imgur.com/WtUP7RW.png

I also have HW Info but it's got so many sensors and readouts and I prefer the simplicity of HW Monitor. Not sure if I'm getting inaccurate readings from any or all of these though.

I understand I'm using stock cooling, but it seems strange to have scores not just below par but well below par in higher core count loads paired with the clock speed dropping slightly below base clock. I don't know if it's a temperature or voltage limit, and how pressing it may be. Temperatures (at least the one lone CPU one I can find) seem fine.

That all said, I'm happy with it over my prior platform. But I'm concerned I'm losing performance I shouldn't be, and I want to learn more about what's what, upgrade the heatsink and fan, and possibly try and settle on a better configuration (I'd prefer a constant all core speed if possible, but not if it loses me a lot of single core boost).

[_I_]

may be the mobo limiting it (power delivery, vrm config/cooling)

it can also be throttling due to cpu cooling (cpu cooler and thermal paste)

and may also be the way that specific cpu wants to run itself
they have multiple ccx and will run each differently depending on load, but it will do the best it can
forcing a higher overclock can force it to throttle sooner and lower than it would by default

[Illusion of Progress]

Motherboard is an Asus ROG STRIX B550-F.

I understand each CPU will perform differently and to its own limits, but my CPU under higher core count loads seem way, way below par. If I was at par and not getting above par results, yeah, I'd get it, but why is it so far below par? That signifies some awful limit somewhere, right?

[_I_]

the cpu will use its best cores first, then its lower performing cores

if you are using the stock cooler do not try to overclock

for most ryzen cpus jsut let them do what they do
if you are comparing stock to oc performance, they will be different

if the case is getting warm, check the fans and airflow

[Spec_Ops_Ape]

Some good discussions here: https://www.overclock.net/forum/10-amd-cpus/
If using the stock AMD Wraith cooler try using a negative offset voltage on vcore of 0.05 - 0.15 volts. Lower vcore means less heat.
Are you using PBO or auto settings for the CPU?

[r.linder]

TSMC says that 1.3v is the safe limit for their 7nm process that AMD uses for Zen2.

The FIT, otherwise known as the Silicon Fitness, usually has a limit based on lottery, which can also scale based on the amount of cores the chip has; a Ryzen 9 CPU usually has a safe limit of around 1.325v while Ryzen 5 may have a bit more leeway and be closer to 1.35v, but it's unique to the chip, part of the lottery.

There's also an issue with current, voltage overshooting, motherboards tricking software into thinking its using less or more voltage than is actually happening, AGESA versions with different generations, etc.
There are quite a few factors, but I myself have noticed that my 3900X can't get the same clocks at 1.35+ that it once could, but it seemingly stays stable for longer at ~1.3.

This is why my recommendation is to never exceed 1.325v when overclocking any CPU, and to be safe if you want your CPU to last closer to 10 years, finding the best clocks while locking voltage to ~1.325v is a good idea. Potential performance loss in the single core could be worth it, we don't know what will happen in 5+ years.

[ericcui1]

Your performance does seem a little off. Cinebench R20 multi thread should score around 4700 on stock. All cores should be working at 3.9GHz to 4Ghz during load.

[ericcui1]

Illusion of Progress eredeti hozzászólása:

Motherboard is an Asus ROG STRIX B550-F.

I understand each CPU will perform differently and to its own limits, but my CPU under higher core count loads seem way, way below par. If I was at par and not getting above par results, yeah, I'd get it, but why is it so far below par? That signifies some awful limit somewhere, right?

What's you RAM speed?

[ericcui1]

Seems to me your temps did not get too hot, so thermal throttling should not be the issue. Maybe resetting the BIOS to default can resolve the problem.

[Bad 💀 Motha]

Guru3d.com has some good reviews on Motherboards and also some outline a good explanation of bios settings particular to said board and many may even contain an overview with regards to Overclocking.

Or simply try Google your Motherboard model (such as MSI B450 Tomahawk Max) followed by words/terms such as: in-depth review -or- overclocking guide

[Illusion of Progress]

Thanks to everyone for the comments so far.

Yeah, searching the internet is showing me that most people are getting ~4750-ish at stock (not overclock) on this CPU. There some in the 4600, one 4500, but I only found one lower than that, and it was someone who had even lower than I did at around 3900, but resetting the BIOS to default got them back up to normal scores. This includes people with B350 and B450 boards running stock, so I can't imagine my B550 or RAM should be dropping me nearly 20% of my score?

So, I tried that. There was an improvement, but something tells me I'm still way off base here.

Here's with everything set to default. RAM is running at 2,133 MHz (not sure about timings) and Infinity Fabric was like 1,200 MHz.

https://i.imgur.com/Ncd4kyD.png

So, I reset, and set D.O.C.P. with Infinity Fabric to 1,800 MHz and nothing else. Ram is running at 3,600 MHz (16-19-19). As in, back to where it was when I got my result posted in the OP.

https://i.imgur.com/DOHtXLA.png

So, uh, I guess my single core score stayed up but that's not my concern. From 2,133 MHz RAM/1200 FCLCK to 3,600 MHz RAM/1,800 FCLCK and I'm losing performance atop my already well below par results. Keep in mind it's not this one benchmark itself I'm really concerned with (another mimics this symptom), but the fact that it may be a symptom of less than normal all core load performance. My scores are basically between a Ryzen 5 3600X and Ryzen 3700X, so I guess I have a Ryzen 6 3650X here.

I'm starting to worry my board or more so RAM choice was bad. Considering I spent the most on RAM (because of quantity), that's disappointing. I knew I wasn't getting top grade stuff, but surely 3600 MHz CL 16 stuff shouldn't be getting me atrociously below par results?

Might need to do more manual exploring. Maybe there's a setting on this board/BIOS I need to set.

[Bad 💀 Motha]

Share the full ram timings when it's at 3600mhz

If the first # is say 16, but the rest are higher... such as say, 16-18-18

Then this could be why.
Review this in CPUZ

You can always try something like 3200mhz and see if you can get the timings lower and tighter.

[ericcui1]

Tested mine in stock configuration, with 3600CL16 RAM, scored 4663 in CB R20.
https://imgur.com/a/64i3ZhK

4400 ish in CB R20 is not that far off I think. Could be some bloatware running in the background.

[Illusion of Progress]

Yeah, I know it's not straight 16 for all the primary timings; it's like 16-19-19, but even with awful RAM, I don't think it'd entirely explain being around 1,000 points or 20% below normal.

Here's a CPU-Z validation link though, in case I'm really overlooking something obvious.

https://valid.x86.fr/8gnpwi

[Illusion of Progress]

ericcui1 eredeti hozzászólása:

Tested mine in stock configuration, with 3600CL16 RAM, scored 4663 in CB R20.
https://imgur.com/a/64i3ZhK

4400 ish in CB R20 is not that far off I think. Could be some bloatware running in the background.

The Windows install is fresh, and I ensured as little as possible was running when doing the benchmarks.

[ericcui1]

Illusion of Progress eredeti hozzászólása:

Yeah, I know it's not straight 16 for all the primary timings; it's like 16-19-19, but even with awful RAM, I don't think it'd entirely explain being around 1,000 points or 20% below normal.

Here's a CPU-Z validation link though, in case I'm really overlooking something obvious.

https://valid.x86.fr/8gnpwi

It's always been hit or miss for Ryzen desktop CPUs to work with 4 RAM sticks. There is definitely something funny happening there. For example, FCLK clock halved on its own.
Lower your RAM speed to 3000~3200, or just take out two of the sticks, see what happens.