Coffeelake thread, benchmarks, reviews, input, everything.

[tamz_msc]

Any reason why CB scaling tapers off after 4.8-4.85GHz on the 8700K?

 

[.vodka]

Throttling? Seems odd.

 

[Dufus]

It is in the Anandtech review:

This change in policy is somewhat concerning and completely unnecessary. The information itself could be easily obtained by actually having the processors and probing the required P-states (assuming the motherboard manufacturer does not play silly tricks), so this comes across as Intel withholding information for arbitrary reasons.

Does this mean one can no longer read the values from the OC Mailbox or that nobody knew how to do it?

 

[moonbogg]

Any reason why CB scaling tapers off after 4.8-4.85GHz on the 8700K?

Probably needs faster RAM?

Only thing that sucks about this chip are the temps. They are basically garbage and can't be fixed. Its a direct die cool or go home chip IMO. None of that delidding and TIM replacement crap would do it for me. I'd just rip the stupid lid off the thing and direct die cool it like a GPU block and watch the temps crash through the mantle.

 

[TheGiant]

finally a worthy release from Intel

I am going to buy it, can't resist

I never had a 5GHz CPU (not one even POSTed at that frequency), but this one is top IPC core and 6 Cores coolable with good air cooler

Goodbye 4.X GHz 4C...

 

[TahoeDust]

Probably needs faster RAM?

Only thing that sucks about this chip are the temps. They are basically garbage and can't be fixed. Its a direct die cool or go home chip IMO. None of that delidding and TIM replacement crap would do it for me. I'd just rip the stupid lid off the thing and direct die cool it like a GPU block and watch the temps crash through the mantle.

The reviewer for HardOCP has a 8600k running 5.2GHz under a custom loop running pretty cool...Core Max 76c after 1 hour of Prime95.

https://hardforum.com/threads/intel...ghz-with-3600mhz-ram.1945332/#post-1043254373

 

[coercitiv]

Any reason why CB scaling tapers off after 4.8-4.85GHz on the 8700K?

Throttling? Seems odd.

Probably needs faster RAM?

It's temp throttling, ain't gonna go higher without delid.

Looking at our power consumption and performance graph, we see a bend at ~4.8 GHz. Power use continues increasing with higher clock rates, but the Cinebench score levels off. A failure to continue scaling at 5.0 GHz is a good indicator that our CPU is throttling. It simply cannot dissipate heat quickly enough.

While we're only measuring an average of 170W, thermal throttling keeps the 180W+ peaks from becoming our average power consumption result. At that point, even the most powerful coolers have to throw in the towel.

Here’s the good news: unless you render or run Prime95 for hours on end, a good air cooler can theoretically handle 4.8 GHz in a well-ventilated case. Intel’s thermal interface material isn't desirable, but it shouldn't stop you from achieving a decent overclock.

 

[beginner99]

I won't let mine run much over 70c sustained loads. ANY of my boxes, Intel Xeons or Ryzens or my TR.

NOTE: All my boxes run 100% load 24/7/365. So someone running occasional loads at 80c may be fine, I just can't deal with that.

Is there any reason not to run at high temps? As far as I know heat damage below tjunc isn't really an issue.

Anecdotal evidence but back in the day with limited money I ran seti@home on a cheapo prebuilt for years, at 90°C. Later gave that one to my parents and it ran for another couple years until the gpu crapped out (and I figured out the mainboard had a defect and you could only run pcie 1.0 cards which weren't available anymore).

 

[DaveSimmons]

But... but...but... It has higher power consumption than the competition!

That really does matter to some of us, for both CPUs and GPUs. Power efficiency that is.

Which is why I'll probably be buying the 8700 non-K instead. Slightly slower at stock, 30 watts less at stock.

 

[.vodka]

It's temp throttling, ain't gonna go higher without delid.

Well, it is expected that the TIM becomes overwhelmed with the heat output of six cores at >4.8GHz. Those >100°C spikes, Intel lists TjMAX at 100°C, so yeah. Not to mention if one loses the silicon lottery and more voltage than usual is required to hit those speeds...

A delid+CLU is mandatory to get the most out of this. Well, that is valid for any TIM'd unlocked Intel CPU since Ivy. The 20-30°C drop is too much to ignore. Has always been.

I saw a screenshot of a benchmark with CPU-z showing 5.2GHz on all six cores, it's insane. I wonder how high can it go properly cooled for 24/7 usage.


Oh, look!

Intel has finally stopped their idiotic artificial segmentation of K and non K parts, they used to disable VT-d on K parts and some other antics, too.. no more! Good to see them come to their senses.

Idiotic PCI-e lane segmentation in HEDT is up next, hopefully.

 

[epsilon84]

That really does matter to some of us, for both CPUs and GPUs. Power efficiency that is.

Which is why I'll probably be buying the 8700 non-K instead. Slightly slower at stock, 30 watts less at stock.

It was a tongue in cheek comment that the 8700K isn't an infallible chip, that the performance comes at a cost of power consumption.

Enjoy your 8700. Its still a hell of a CPU.

 

[tamz_msc]

Is there any reason not to run at high temps? As far as I know heat damage below tjunc isn't really an issue.

Anecdotal evidence but back in the day with limited money I ran seti@home on a cheapo prebuilt for years, at 90°C. Later gave that one to my parents and it ran for another couple years until the gpu crapped out (and I figured out the mainboard had a defect and you could only run pcie 1.0 cards which weren't available anymore).

Well higher temperatures will dump more heat into the external environment. A PC is an open system at the end of the day.

 

[R0H1T]

I was hoping the multicore enhancement would work on non-K CFL, I remember having seen someone claim to have it working on a locked KBL i5... but I could not find the reference anymore.

However, the fallback option to the 4Ghz was continuous 3.8Ghz boost, and that seems to be in the cards.


Performance in reviews is all over the place: CB15 "stock" performance varies from the ~1300 score on Guru3D to the ~1440 score on the Techpowerup. It's probably a combination of immature BIOS plus different default configuration the motherboard maker chooses to implement (max MT turbo clock, uncore frequency, power limitations etc)

If you want a more clear image for performance and power in CB15 I suggest you take a look at this chart from Tomshardware:

Scratch that, seems there's more info needed here.

 

[Whitestar127]

@Markfw: Will you update the OP with a collection of reviews?

 

[beginner99]

Well higher temperatures will dump more heat into the external environment. A PC is an open system at the end of the day.

if the PC uses the exact same amount of energy, it doesn't matter if the CPU is 50° or 100°, the room will warm up for the same amount.

I literally mean "running hot" and not "using lots of power". If the cpu is cooler at it means is the heat is moved away from it faster. But there will be no effect on room temperature or needed room cooling.

 

[StrangerGuy]

That really does matter to some of us, for both CPUs and GPUs. Power efficiency that is.

Which is why I'll probably be buying the 8700 non-K instead. Slightly slower at stock, 30 watts less at stock.

Yeah, I don't see the point OCing mainstream Intel i7s since 4790K when they are already clocked so high with little headroom that they are already running close to their thermal limits at stock. A ~10% OC with a ton more power draw for an imperceptible real world impact isn't my cup of tea. The main reason to get a Z-board is now for DDR4 >2666 than actual CPU OCing.

 

[epsilon84]

Yeah, I don't see the point OCing mainstream Intel i7s since 4790K when they are already clocked so high with little headroom that they are already running close to their thermal limits at stock. A ~10% OC with a ton more power draw for an imperceptible real world impact isn't my cup of tea. The main reason to get a Z-board is now for DDR4 >2666 than actual CPU OCing.

5GHz just sounds badass though! Of course when you overvolt a CPU, things start getting toasty. Its a bit more than a 10% overclock though, unless you are comparing it more to the max single core boost (4.7GHz) rather than 6 core boost, which is 4.3GHz. Some chips are even gettting to 5.2GHz which would represent a ~21% overclock vs 4.3GHz, albeit with a massive power consumption penalty. Now, is a 15 - 20% performance gain perceptible? Perhaps, perhaps not. But it's good that we have that option. For those that want efficiency, there is the 8700 non K.

 

[LTC8K6]

Why wonder if it's throttling when you can use something like XTU to actually see the throttling on a graph?

 

[RichUK]

 

[tamz_msc]

if the PC uses the exact same amount of energy, it doesn't matter if the CPU is 50° or 100°, the room will warm up for the same amount.

I literally mean "running hot" and not "using lots of power". If the cpu is cooler at it means is the heat is moved away from it faster. But there will be no effect on room temperature or needed room cooling.

But you can't have a CPU at a fixed frequency consuming the same power at 50 or 100 degrees.
https://forums.anandtech.com/thread...-power-consumption-with-the-i7-2600k.2200205/

 

[DrMrLordX]

Have a few drinks. Everything follows a bell curve.

Pfft. Anything is possible if you get sufficiently drunk. Next you will be telling me that AMD gamer fangirl babes will come riding in on pink unicorns. Or that Vega will actually sell for initial MSRP.

Due to Intel not increasing IPC and only clocks and cores, AMD needs to hurry up and make 4ghz+ Ryzen's already.

Not the right thread dawg.

Real gem are R5 1600/X. Well for that price all them are GEMS.

Definitely not the right thread.

the 1600 needs a price drop,

Got a separate thread for that one.

As a gamer I recommend you to buy R5 1600

Argh why why why

I think Ram above processor supported speed speed is almost non relevant, don't know why you are making such a big deal

Benchmarks have shown almost no gains on ram oc

Wat.

Were you uh . . . not paying attention to the 7700k RAM scaling benchmarks? I estimate that the 8700k will want DDR4-3600 minimum to scale properly in workloads that fully-utilize 12 or more threads.

Oh yeah, if you have the TOP cpu and SLI of the TOP gpu then it "may" be "useful", because only then, the ram is bottleneck and even not the same result on all games.

I was generalizing as most people may have a top tier cpu, and ONE top tier gpu, in that case the difference is meh. And that's most people

Um.

Probably needs faster RAM?

Thermal throttling aside, YES

 

[TheLycan]

Pfft. Anything is possible if you get sufficiently drunk. Next you will be telling me that AMD gamer fangirl babes will come riding in on pink unicorns. Or that Vega will actually sell for initial MSRP.



Not the right thread dawg.



Definitely not the right thread.



Got a separate thread for that one.



Argh why why why



Wat.

Were you uh . . . not paying attention to the 7700k RAM scaling benchmarks? I estimate that the 8700k will want DDR4-3600 minimum to scale properly in workloads that fully-utilize 12 or more threads.



Um.



Thermal throttling aside, YES

This what happens. You are complaining about AMD discussions here but forgot this aint 7700k thread either. Why newbies want to stay in front of the line?

 

[DrMrLordX]

This what happens. You are complaining about AMD discussions here but forgot this aint 7700k thread either. Why newbies want to stay in front of the line?

So you must have missed all the thread derailments. Dude Kabylake is literally the exact same uarch as Coffeelake, with just two fewer cores, on a slightly less-mature version of the 14nm process. How can you NOT compare Coffeelake and Kabylake, if only to confirm that adding more cores produces desirable scaling (generally it does)? Cmon now. And what newbies are we talking about here?

Seriously, we already ruined some other threads by people bringing off-topic brand loyalty nonsense into product-specific discussions. It should be obvious that we don't want people running in here promoting or bashing AMD products in a Coffeelake thread.

 

[tvdang7]

ouch LOL

 

[CHADBOGA]

moonbogg is in shock mode.

Don't worry, the fun is just getting started, looks like 2018 will bring more of the same.

Whilst just like Kylo Ren and his battles with the pull to the Light Side of the Force, so too do I feel the pull to Moar Cores, but what I really want to see is some significant single threaded performance increases, which then benefit every core.

I said previously that when I do finally upgrade my i5 3570K @ 4.0Ghz, I wanted it to be to an 8 core version of the best performing single core CPU and for it to be an easy 24/7 overclock to 5 Ghz.

I was told I was being a bit too ambitious in my hopes, but with what the 8700K is showing, I hope that by 2020/1, I will get the CPU I previously mentioned I would want.