Intel's 8th Generation Core Family - Coffee Lake (LGA 1151, 6C/12T)

Where do you expect Core i7-8700K's Turbo to land?

  • 3.8/3.9 GHz

    Votes: 0 0.0%
  • 4.0/4.1 GHz

    Votes: 3 23.1%
  • 4.2/4.3 GHz

    Votes: 6 46.2%
  • 4.4/4.5 GHz

    Votes: 3 23.1%
  • 4.6/4.7 GHz

    Votes: 1 7.7%

  • Total voters
    13
  • Poll closed .
It's more that I just don't think its entirely accurate to say its a 5ghz overclock if in the most demanding situations its actually running at 4.8ghz (and as I said, a lot of games that aren't even that demanding but trigger AVX instructions thus the throttling). I'm more than happy that my CPU can run all cores/threads at 4.8ghz under any situation, just took a delid, watercooling and lots of voltage to get there. Which is why I roll my eyes when I see people claiming huge overclocks with equivalently huge avx offsets, just feels like it defeats the purpose a bit.
Why would you want to run "4.8GHz under any situation" when you could run 5GHz with a -2 AVX offset at most likely the same temps and voltage? Just so you can feel better about saying what your overclock is without having to specify an offset?

Get used to people using AVX offsets in their overclocks. It is there for s reason. As core numbers increase it becomes more necessary. x299 can really become a fireball without it.
 
Why would you want to run "4.8GHz under any situation" when you could run 5GHz with a -2 AVX offset at most likely the same temps and voltage? Just so you can feel better about saying what your overclock is without having to specify an offset?

Get used to people using AVX offsets in their overclocks. It is there for s reason. As core numbers increase it becomes more necessary. x299 can really become a fireball without it.

There's nothing wrong with using avx offsets, but I overclock to get better performance in situations that actually demand it, meaning CPU intensive applications or gaming (ones that probably use AVX instructions anyway), not to feel good about loading up Firefox or notepad faster at 5ghz. If more applications than not are triggering the AVX downclock it starts to feel counter intuitive to run these insanely high overclocks with avx offsets and claim 5-5.2ghz. All I was saying is that the overclocks look huge on paper but what they're really saying when they say "5ghz overclock with -2 avx offset" is "5ghz but not in this, this, this or this and this".
 
There's nothing wrong with using avx offsets, but I overclock to get better performance in situations that actually demand it, meaning CPU intensive applications or gaming (ones that probably use AVX instructions anyway), not to feel good about loading up Firefox or notepad faster at 5ghz. If more applications than not are triggering the AVX downclock it starts to feel counter intuitive to run these insanely high overclocks with avx offsets and claim 5-5.2ghz. All I was saying is that the overclocks look huge on paper but what they're really saying when they say "5ghz overclock with -2 avx offset" is "5ghz but not in this, this, this or this and this".
Yeah, not much difference between 5 and the 4.8. Maybe it's more epeen. I did not even try for higher on my 5960x. It runs everything just fine.
 
There's nothing wrong with using avx offsets, but I overclock to get better performance in situations that actually demand it, meaning CPU intensive applications or gaming (ones that probably use AVX instructions anyway), not to feel good about loading up Firefox or notepad faster at 5ghz. If more applications than not are triggering the AVX downclock it starts to feel counter intuitive to run these insanely high overclocks with avx offsets and claim 5-5.2ghz. All I was saying is that the overclocks look huge on paper but what they're really saying when they say "5ghz overclock with -2 avx offset" is "5ghz but not in this, this, this or this and this".

I think you may be overestimating the amount of "CPU intensive application" and games trigger the AVX offset. I rarely see my AVX offset kick in except for when encoding. I play a lot of AAA gaming titles and if I ever see it kick in, it is almost always briefly.

I understand exactly what you are saying, and I had the same thoughts when overclocking my 7820x. I kind of felt like I was cheating. In the end after a few months of use, I can see that my machine certainly does not use AVX as often as it doesn't...and I didn't build it to play mindsweaper. If I overclocked to the lowest common denominator, AVX-512 in my case, I would be leaving a ton of performance on the table.
 
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The AVX offset was kicking in under both PUBG and Heroes of the storm which I've been playing a lot of lately, I'm admittedly more GPU bound anyway since I'm using a 1080 (non-ti) but I did find it annoying since neither of these games were going to turn my system into a fireball like Prime95 would.
 
not to mention things optimized to use AVX heavily that require the offset are worlds faster due to AVX and AVX-512, take encoding for example, 4.5 ghz avx-512 encoding absolutely rips and the benefits far out weigh the reduced clocks to make it possible.
 
The AVX offset was kicking in under both PUBG and Heroes of the storm which I've been playing a lot of lately, I'm admittedly more GPU bound anyway since I'm using a 1080 (non-ti) but I did find it annoying since neither of these games were going to turn my system into a fireball like Prime95 would.
Hmmm...I play PUBG also. I don't remember how much it actually kicks in. Maybe I will log my clocks and see how often the AVX offset is kicking in.

Edit: I read yesterday that there may be a bios issue on z270 boards falsely triggering the offset. I dismissed it, but this may be correct. I just tested PUBG and I am deffinitely not seeing the offset kick in except very rarely.
 
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The AVX offset was kicking in under both PUBG and Heroes of the storm which I've been playing a lot of lately, I'm admittedly more GPU bound anyway since I'm using a 1080 (non-ti) but I did find it annoying since neither of these games were going to turn my system into a fireball like Prime95 would.
See my post above about there possibly being a bios issue.

Here is my machine running PUBG. Sorry for the "amateur hour" video, but it was the easiest way for me to share what I am seeing. When I am showing my performance statistics, you can see that the CPU is more or less locked at 4.8GHz on all 8 cores. My current overclock is 4.8GHz with a -5 AVX offset. You can see it goes to 4.2GHz for a second at ~0:13...something must be briefly triggering the offset.

If you are seeing your offset kicking more often, something else is amiss.

 
Interesting. I'll have to try it again and see if the offset is kicking in consistently or not, it was when I last tested but I'll try again soon and see what's up.
 
Built my Coffee Lake rig over the weekend.

8700k (Batch L730C348) (No-Delid)
Thermaltake Floe 360 AIO
Maximus X Hero Wifi AC
32 gb Trident Z RGB 3600 c17

My bios settings are as follows:

AI OC Tuner: XMP
ASUS MCE: Disabled
SVID Behavior: Auto
AVX Negative Offset: 0
CPU Core Ratio: Sync All Cores
1-Core Ratio Limit: 48
CPU SVID Support: Auto

CPU LLC: Level 6

Long Duration Package Power Limit: 4095
Short Duration Package Power Limit: 4095
IA AC Load Line: .01
IA DC Load Line: .01

CPU Core/Cache Current Limit Max: 255.5

CPU Core/Cache Voltage: Adaptive Mode
Offset Mode Sign: -
Additional Turbo Mode Cpu Core Voltage: 1.30
Offset Voltage: .02
CPU VCCIO Voltage: 1.15
CPU System Agent Voltage: 1.2

No crashes or errors in OCCT, Real Bench or Cinema Bench. No Event Viewer errors. HW Monitor shows core at 1.3v Temps top out at 85c. 5Ghz wasnt stable at 1.4v and I don't have the balls/cooling to take it any higher and delid.

Going by what people are posting online, these are pretty underwhelming results.
 
I mean 1.3v 4.8 ghz? thats great if you want 5+ ghz you need more voltage and due to it being a 6 core that means delid and good cooling. if these cpu's could do 5 ghz out the box they'd ship them to do that you need to be able to cool the beast to put the voltage to it to make it possible.
 
Can someone give me a brief explanation of what this AVX stuff is? I'm gathering it's something about using a higher frequency in certain situations? Google's explanations were uh, not user friendly.
 
Can someone give me a brief explanation of what this AVX stuff is? I'm gathering it's something about using a higher frequency in certain situations? Google's explanations were uh, not user friendly.

Its vector instructions. They can run at up to 512bit. AVX2 runs at 256bit.
 
Can someone give me a brief explanation of what this AVX stuff is? I'm gathering it's something about using a higher frequency in certain situations? Google's explanations were uh, not user friendly.

Consider you have to obtain the total monthly sales of four stores.

In the first approach you do all the work in a serial way. First get S1 sales, then S2 sales,...

scalar approach
Code:
          you
day 1 --> S1
day 2 --> S2
day 3 --> S3
day 4 --> S4

In a second approach you get the help of three friends and all you work together, with each one of you working in the data of a single store.

vector approach
Code:
          you  1st-friend  2nd-friend  3rd-friend
day 1 --> S1   S2          S3          S4

Something similar happens with x86 vs AVX.

x86 is scalar architecture. It defines operations apply to one datum at one time. The general acronym is SISD (Single Instruction on Single Data). AVX is SIMD architecture. It defines operations that apply to multiple data at one time. SIMD = Single Instruction on Multiple Data. With AVX instructions a CPU can do more work in the same time, because increases the degree of parallelism.

IntroMICShortFig3c_simd.jpg
 
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Recommendations on a mobo? I bought an Asus Z370-F Gaming but I'm thinking I may be better off with an Asrock K6 or Gigabyte Gaming 7.
 
Recommendations on a mobo? I bought an Asus Z370-F Gaming but I'm thinking I may be better off with an Asrock K6 or Gigabyte Gaming 7.
you looking at any specific features? I am loving my gigabyte gaming 7, solid with the all core 4.7 i havent tried much more but i do like the look of it, and i use 2 nvme in raid 0 and a sata m2 so i kinda need 3m.2.

Also using 4x8gb trident z rgb at 3200 14-14-14-34 with no issues and it fits my kraken x62(just barely) the tubing touches slot one
 
Gaming M5, Taichi, Gaming 7, depending on how much you want to spend.
The Gaming 7 was $199 last week.

No Asus. This is what I'm saying! Haha.

I don't care about built in wifi or on board sound. I care about a good warranty/support. The highest overclock "features" available. ie: decent vrm cooling, power distribution, etc.
 
Does the Asus z370 bios allow you to control each core's voltage individually? This is an option on their x299 boards.
 
Its vector instructions. They can run at up to 512bit. AVX2 runs at 256bit.

Consider you have to obtain the total monthly sales of four stores.

In the first approach you do all the work in a serial way. First get S1 sales, then S2 sales,...

scalar approach
Code:
          you
day 1 --> S1
day 2 --> S2
day 3 --> S3
day 4 --> S4

In a second approach you get the help of three friends and all you work together, with each one of you working in the data of a single store.

vector approach
Code:
          you  1st-friend  2nd-friend  3rd-friend
day 1 --> S1   S2          S3          S4

Something similar happens with x86 vs AVX.

x86 is scalar architecture. It defines operations apply to one datum at one time. The general acronym is SISD (Single Instruction on Single Data). AVX is SIMD architecture. It defines operations that apply to multiple data at one time. SIMD = Single Instruction on Multiple Data. With AVX instructions a CPU can do more work in the same time, because increases the degree of parallelism.

IntroMICShortFig3c_simd.jpg


iirc avx use a ton of memory bandwidth and with just dual channel it seems hitting the limit, going to avx2 prob will see some improvement but prob not much if stayed on dual channel. with 8 cores and avx512 we will need at least 4-6 channel of memory to full take advantage of that $h!t which is why skylake-x was so appealing but then the junk mesh clock ruined it at only 3300mhz max. if it can do over 4000mhz on mesh totally worth it.

Cannon Lake is mobile only and dualcore Y segment. The next step for desktop is Icelake.

More CFL SKUs are coming in Q1. Z390 isn't tho.

missed SL's 8700k sale by like less than 1 min literally all sold out on checkout page, when is 8 core CFL or icelake coming, 8 core 10nm+ would be nice.
 
It uses a ton of cache bandwidth yes. Not so much system.

EPYC loses massively to SKL for the same reason. 3x perf delta. EPYC sales are counted in a couple of 100 units because of bugs and because AMD went cheap on AVX support.
 
It uses a ton of cache bandwidth yes. Not so much system.

EPYC loses massively to SKL for the same reason. 3x perf delta. EPYC sales are counted in a couple of 100 units because of bugs and because AMD went cheap on AVX support.

how credible is this source this person getting from?
 
how credible is this source this person getting from?

We use some of those vendors (the big ones) and I have posted before that they have nothing with AMD CPU's on their roadmaps so far...the info sounds very credible to me.
It's sad when reality and forums/PR are so far apart...when you read the forums/PR you get the impression that Intel is under pressure...when I look at our datacenters...I see nothing but Intel CPU's *shrugs*
 
I pulled the trigger and I've ordered:

- 8700k
- gigabyte gaming 7
- gskill ripjaws V ddr4 16gb 3200 14CL
- Seasonic 850w Focus Gold PSU
- Samsung 960 Evo 250gb NVMe
- noctua d15

This will go into my old trusty HAF 922. No more excuses for GTX1070 ;-) This should be good upgrade from [email protected]

I will report back once the system is up and running in a week or two. ;)


Recommendations on a mobo? I bought an Asus Z370-F Gaming but I'm thinking I may be better off with an Asrock K6 or Gigabyte Gaming 7.

Based on what I've read I would go with Gaming 7 (best VRM out of the 3). For Asrock K6 or Taichi there is fets lottery and you might get either fairchild & sinopower. (You want fairchild).
I was deciding between Asus Hero X and Gaming 7, both with great VRM sets for overclocking. I went with Gaming due to the cheaper price.
 
https://wccftech.com/intel-z390-motherboard-leak/

Bend over and get the lube, Intel is coming at you again earlier than expected.
As long as the CPUs are forwards/backwards compatible, they can launch as many chipsets as they want.
Nobody ever complains about having too many choices unless, of course, it's Intel apparently. :p

Obviously if they are using Z390 to gate 8C Coffee Lakes, that's a separate problem entirely.
 
As long as the CPUs are forwards/backwards compatible, they can launch as many chipsets as they want.
Nobody ever complains about having too many choices unless, of course, it's Intel apparently. :p

Obviously if they are using Z390 to gate 8C Coffee Lakes, that's a separate problem entirely.

I haven't seen 8C compatibility on Z370 anywhere. The same people that are claiming 8C compatibility were the same ones claiming Z270 CFL compatibility and we know how that worked out.
 
As long as the CPUs are forwards/backwards compatible, they can launch as many chipsets as they want.
Nobody ever complains about having too many choices unless, of course, it's Intel apparently. :p

Obviously if they are using Z390 to gate 8C Coffee Lakes, that's a separate problem entirely.

It is pretty fucking annoying though. I went ahead and pullled the trigger on Z370 because 390 was too far off for my needs. When they launch it much earlier than expected I've now made a mistake because they can't get their shit together. But as has been mentioned, if I can drop in an 8 core then it mitigated. I won't hold my breath.

The whole Z270 / Z370 / Z390 thing is pretty irritating and definitely motivates me to go AMD next time.
 
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