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mattebad

In Depth Skylake Overclocking Guide from Overclock.net

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Posted · Original PosterOP
 
 
Welcome to the Skylake Overclocking Thread. Because a lot of people found my Haswell Overclocking Guide to be a useful source of information, I have decided to try my hand at a Skylake guide as well. For those new to Overlock.net, know that you can open an image in a new tab to view it in its actual size.
 
 
 
I am not responsible if your CPU blows up, your motherboard blows up, your computer blows up, your house blows up, or if your life blows up due to my guide.:buttkick: 
 
 
My recommendations on what parameters are "safe" are my opinions. I do not have many chips I can subject to high voltages and loads to figure out what is truly safe or unsafe.
What is Skylake?
Skylake is the codename of the microarchitecture launched at August 2015 to succeed Broadwell. The unlocked desktop parts were the first to come out. They are the i5-6600k and the i7-6700k.
 
How are the 6600k and the 6700k different?
It's the same pattern as in previous generations.
 
6600k:
Base Clock: 3.5GHz
Max Turbo: 3.9GHz
L3 Cache: 6MB
Hyperthreading: No
Box Cost: $243
 
6700k:
Base Clock: 4.0GHz
Max Turbo: 4.2GHz
L3 Cache: 8MB
Hyperthreading: Yes
Box Cost: $350
 
In most cases the L3 cache difference is immaterial. If you want hyperthreading, the choice is obvious but bear in mind it makes the CPU hotter in testing. Will the i7 part overclock better? That remains to be seen. However, if my

Haswell Overclock Chart

is any indication, the difference will likely be small. If that 100MHz matters that much to you, you should've bought a binned chip in the first place.
 
What's new with Skylake?
  • No stock heatsink.
  • z170 chipset.
  • Socket 1151. Past coolers compatible with Sandy Bridge, Haswell, etc still work.
  • Neither the CPU nor the socket are backwards compatible.
  • Removal of Fully Integrated Voltage Regulator, or FIVR introduced at Haswell due to issues at low power applications.
  • Lack of FIVR may mean lower temperatures (although that's just one factor among many) and could mean better response under extremely low temperatures.
  • According to Sin from OCN and Raja from Asus, changes in architecture requires less robust power-handling components. Because of this, boards tend to have a lower power phase count.
  • DDR4 is standard. DDR3 and DDR3L support very rare, and no motherboard supports both DDR3 and DDR4. Still dual channel memory controller.
  • It is believed that the Integrated Memory Controller in Skylake is very strong, allowing very high speeds without compromises.
  • A smaller die, thinner PCB, and smaller process than Haswell/Devil's Canyon.
  • Generally acceptable core voltage has increased.
  • Expect overclocks to be similar to that of DC. (In this guide I will refer Haswell as Haswell and Haswell Refresh as DC.)
  • Base clock can be changed in a very fine-grain way. Instead of "straps" jumping for 100 to 125 MHz etc, now you can increase it 1 MHz at a time. It's also possible to deviate from the base clock more without instability. Changing the base clock here has no effect on the DMI. However, it still affects ram and PCIE. In total, this makes BLCK changes a more useful thing to try.
  • In a similar spirit, ram overclocking is less granular. What used to be 200/266 MHz steps are now 100/133 MHz steps.
  • Power usage is similar enough to DC/Haswell. Temperatures similar to DC.
  • Graphics updated to HD 530.
What about the "x20 PCIE lanes" stuff I've been hearing about?
  • The Direct Memory Interface has been upgraded to version 3. This bumps up the spec to 8.0 gigatransfers per second.
  • There are "20 lanes of PCIE 3.0". 16 are direct lanes to the CPU. If you want more you need to go to the enthusiast platform.
  • The remaining 4 lanes are handled by the DMI. In the past you had 2 GB/s cap, now you have 4 GB/s cap. There's still overhead, so in reality you'll get maybe a maximum of 3.5 GB/s. You can now run a single Intel 750 Series ssd without bottlenecks. DMI PCIE lanes have a higher latency than direct CPU lanes but the difference should be minor. You can now RAID PCIE ssds through Intel Rapid Storage Technology, and it can be a mix of NVMe and ACHI drives, although that is not recommended. Procedure remains tricky.
  • The DMI upgrade also means you will be seeing a lot of new USB 3.1 ports, with a chance of seeing USB Type-C ports. Of course, if all of those are running at full blast, expect your PCIE SSD speeds to suffer a bit.
  • Usually in motherboards, the top PCIE lane is x16 PCIE 3.0 lane, second is the same, and the third full PCIE lane is for the SSD. Since Skylake CPUs only have 16 CPU PCIE lanes, putting a second GPU in means both GPUs run at x8.
 
 
How does Skylake stack up to past generations?
Refer to this lovely chart from PCPer.
 
 
 
 
(Credits: PCPerspective at www.PCPer.com)
 
Haswell overclocked to ~4.5GHz and DC maybe ~4.6-4.7Ghz. It's far too early to say what the average Skylake overclock will be. Clock for clock Skylake has an extra large improvement in x264, of about 28% over Snady Bridge. The chart might be using an old version of x264 though. Other sources report 35% gain. In Cinebench however, that lead shrunk to 11% over Haswell and 25% over Sandy Bridge. Broadwell isn't often discussed due to low TDP, probably low overclocking, and the emergence of Skylake.
 
Quick Word about Temperatures and Delidding:
 
Intel said that Skylake has a similar thermal solution under the Integrated Heat Spreader to that of Devil's Canyon. The temperatures are also similar to DC when I consider margin of error. However, it still benefits from delidding. Expect 10-13C improvement in temperatures. Lower temperatures can decrease the amount of voltages required to stabilize. By delidding yourself, you are risking permanent destruction of your CPU and resale value of the CPU will decrease even if the delidding went perfectly. You can pay $50 to SiliconLottery to have them delid it for you. This service is insured so that if anything does go wrong, your chip will be replaced.
 
There are also two types of delidding. You can either choose to take off the IHS, put on paste, and mount the cooler directly onto the die. This is called 'bare-die' and requires a more delicate touch. If the cooler is mounted too tightly you can warp the die and you're toast. If you elect to put the IHS back on, this is the safer method. Bare die isn't a large improvement over putting the IHS back on, so I recommend putting the IHS back on.
 
Is there any insurance for my CPU?
Yes. The Intel Protection Plan still exists. For $25-$30 you can stop worrying about overclocking leading to death of your CPU. This is on top of the warranty you get with a CPU purchase. Visit

here

for details. In general people found that Intel has been pretty lenient in accepting replacements.
Here are some things to think about before the instructions are read:
  • Coolermaster 212 Hyper Evo -> Noctua D14 -> x61 Kraken -> Custom Loop
  • Do you want to delid?
  • Ripjaws 4 were out during the x99 times, which is pre-Skylake. Both Ripjaws 4 and Ripjaws 5 are DDR4 modules, but it is recommended to use the latter. There have been some anecdotal reports of Ripjaws 4 requiring more voltage to be stable on the z170 platform.
  • Unlike Haswell, LLC affects core voltage like the pre-Haswell times, and adaptive voltage mode is no longer dangerous under heavy synthetic loads like Prime95.
  • On a similar note, input voltage is no longer a setting. Same goes for cache voltage.
  • C-states decrease the voltage and in turn power usage during idle. This has a marginal effect on SSD performance.
  • The recommended utility for looking at your stats is HWInfo available

    here

  • Terminology Check:
Uncore = Cache Ratio = Ring Bus (Not technically 100% true, but when people say these things that's what they mean.)
BLCK = Base Clock
100 (Base Clock) x 45 (Multiplier) = 4500MHz or 4.5GHz
 
Again, changing the base clock affects PCIE and ram speeds. You will have to readjust the ram setting accordingly if you change the base clock.

 

Skylake is still a new launch. Keep track of BIOS updates. Things may be improved as time passes.
 
  • If you Bsod, you can look at some details from the crash log. BluescreenView will pull up the information for you. If you want, you can download it

    here

  • VID is the voltage the processor requests. Generally it is not a useful reading in HWinfo. Vcore when read in real-time in a tool like HWinfo is a measurement of the voltage actually given. When you put in 1.3v into core voltage in the BIOS, maybe only 1.25v is given to the cores under load. This discrepancy is called Vdroop. To counteract that you can simply raise the voltage you entered or you can use Load Line Calibration or LLC. This setting impacts the real-time Vcore reading and increases it. Voltage delivered can have very quick drops, so quickly that specialized gear is required to detect it. LLC helps counteract that.
 
 
 
  • Whenever possible, change as few settings at a time. If you crash with core, cache, ram, and GPU overclocks enabled, it's hard to tell which overclock(s) caused the crash.
  • Increase multiplier by 1 each time.
  • The voltage required to stabilize the next multiplier increases each time.
  • Write down the settings you've tried for better organization.
 
 
 
Skylake comes with far more freedom to tweak than Haswell, but this also means more complexity when you are in pursuit of the absolute best settings possible.
 
0. Update your UEFI.
 
1. Manually set your cache ratio and ram to stock. Don't even use XMP profiles. Hell, turn your GPU's overclock off.
 
2. All Skylake CPUs so far can hit 4.4GHz. Try 4.4GHz at ~1.35v. It should work and be stable. If not, apply 1.4v. Stable? Good.
 
3. Just go up a multiplier. Increase voltage if you crash during stress testing with our x264 test. Remember, recommended maximum voltage is 1.45v. Never run a stress test and leave without monitoring the temperatures for the first 2 minutes.
 
4. Eventually you will find the highest overclock you can hit without breaking 1.45v and this overclock will pass x264 test overnight. Another option is to try Prime95 v27.9, but v28.7 is overkill and masochistic. To read more about different stress tests and to access quick download links to them (including out modified x264 test), check the "Stress Testing" spoiler.
 
5. Decide if you want to tweak the base clock. The next section is all about that. If you don't want to tweak the base clock, continue reading about Fclk if you want a possible 1% boost to your FPS in graphics-related stuff like gaming and skip to ram overclocking and cache overclocking. The sections with a blue title are related to base clocks, but the Fclk section applies to those who want to tweak Fclk without touching the base clock as well.
 
 
Blck/Fclk tweaking time!
 
Blck, or "base clock", affects multiple things including: Fclk, core frequency, cache frequency, and ram frequency. Let's look at each of these things.
 
Fclk (Optionally with Base Clock Changes):
 
Fclk is a setting that has to do with the way the GPU contacts the CPU. The default setting was supposed to be 1000MHz, but due to some complications, z170 boards end up having 800MHz as the default setting. The ability to adjust the Fclk was added with later BIOS updates. Fclk is a GPU-oriented setting, so CPU benchmarks won't notice a difference. The difference between various Fclk settings is relatively small. It varies depending on the configuration (especially from GPU to GPU), but for a 980ti the difference is within the margin of error. Open the spoiler here to look at Anandtech's results:

 
Notice how different the gains are depending on the GPU used.

800MHz is the default, with 1000MHz being an option, but it's possible to overclock this further.
 
 
There should be a setting to adjust the Fclk directly in your BIOS, allowing you to set the Fclk to 400MHz, 800MHz, or 1000MHz. 
 
For example, in the Asus Hero z170 UEFI, under "Tweaker's Paradise", there is an option called "FCLK Frequency for Early Power On". With all motherboards there is typically an option for 1000MHz. What this setting actually does is set the Fclk multiplier to 10, and if the base clock is 100, 100 x 10 = 1000MHz Fclk. In HWinfo, under "System Agent Clock" (refer to Overclock Preparation spoiler), it should now read 1000MHz.
 
So, if you choose to only overclock the Fclk through the dedicated Fclk setting, make sure your base clock makes sense. If you have it set to 1000MHz and you forget about it and you go back to changing the bclk to overclock your core clock, you won't understand why you won't POST at 170 bclk. The answer is that your Fclk has been overclocked to an insane value.
 
So let me state it again: Your final Fclk frequency is affected by both your Bclk and the setting you've chosen in the dedicated Fclk setting.
 
Fclk setting at 1000MHz (Fclk multiplier = 10)
Bclk set to 100MHz
-----------------------------
10 x 100 = 1000
Fclk is 1000MHz
 
 
Fclk setting at 800MHz (Fclk multiplier = 8)
Bclk set to 110MHz
-----------------------------
8 x 110 = 880
Fclk is at 880MHz
 
If you didn't pick a Fclk setting and you left it at auto in the dedicated Fclk menu, then your motherboard will try to adjust the Fclk multiplier so that you will not crash.
 
 
Fine tuning Core Clock with Base Clock:
 
Base clock x Multiplier = frequency in MHz
 
Recall that multipliers can only be whole numbers. If we only tweak the multiplier, we can only do 4.5, 4.6, 4.7GHz etc. What if I can do 4.5GHz but I cannot do 4.6GHz? Maybe I can stabilize 4.55GHz. To get 4.55GHz we have to change the base clock. The base clock can contain decimals (like 100.1MHz, etc).
 
So let's say we want to do just that: Apply a 4.55GHz core clock. We know our 4.5GHz overclock is stable and this is our fallback. Let's pick a number that's kind of close to 100 that multiplied by something gives us 4550. 130 base clock with 35 core multiplier will do just that.
 
Old OC:
100 x 45 = 4.5GHz Core clock
100 x 40 = 4.0GHz Cache clock
2133MHz Memory clock
 
Base clock set to 130:
130 x 45 = 5.85GHz Core clock
130 x 40 = 5.20GHz Cache clock
2773MHz Memory clock
 
Base clock set to 130 and multipliers adjusted accordingly:
130 x 35 = 4.550GHz Core clock
130 x 31 = 3.900GHz Cache clock
2080MHz Memory clock
 
If the above passes, we now have a stable 4.56GHz. Maybe we could aim for 4.57GHz now.
 
In the example, changing the base clock to 130 causes the core, cache, and memory clocks to be far higher than stock. (Why stock? Because if you were following directions, all of your overclocks should be set back to stock!) Since the cache and ram are now overclocked, we don't know if the new cache and ram overclocks are stable, and if the new settings crash we don't know if it's the core clock, cache clock, or memory clock causing the problem. We must adjust the multipliers to set it back to stock. 31 as the multiplier for cache gives us something close to what it was originally, so we will not crash. Setting the ram back down to close to 2133MHz gets us stable ram once again.
 
The higher you go from 100 base clock, the harder it is to stabilize. Generally the stability at 170 bclk and up will vary depending on the motherboard. You will sometimes fail to boot if the bclk is too high. There's usually no good reason to set the base clock above 170 though. With smart math, it should be possible to get very close to any frequency without exceeding 150 bclk. Don't forget that bclk can have decimals.
 
Base Clock Balancing Act:
 
If you want to adjust the Fclk and ram settings on top of fine tuning core and cache clocks with base clock changes, you have to ensure that:
  • Bclk that is not too far from 100 to cause instability.
  • Bclk when combined with a core multiplier, gives you the absolute highest core frequency that is stable.
  • Bclk when combined with a Fclk multiplier (4, 8, or 10) has to result in an overclocked, but stable Fclk.
  • Bclk when combined with a right memory divider, gives you a ram frequency that is overclocked somewhat near its maximum.
 
 
 
Ram Overclocking
 
Once both the core and cache ratio are set to stable and overclocked values you don't want to touch anymore, go ahead and overclock your ram. You now have more fine-grain jumps in frequencies to choose from. Don't forget that timings matter as well, and the "tighter" or the smaller the numbers are, the better. According to Asus, System Agent and VCCIO voltages can help stabilize a ram overclock, although more isn't always better. The ram itself could use some extra voltage. The default is 1.3v, let's bring that to 1.35v which is a safe amount.
 
Here are rough guidelines for figuring out how your ram is doing for those too lazy to benchmark:
 
Latency:
Ram can have lower latency or higher frequency. Generally for gaming purposes, lower latency is considered to be more important (unfortunately for you, DDR4 is generally worse in this regard than DDR3). To calculate latency, do 2000 x (Cas/Frequency). Lower is better.
 
Frequency:
On the other hand, a higher frequency is generally considered to be useful for video editing workloads which do sequential reads. These types of work favors higher frequency. To calculate how long these reads take we do 1000/Frequency. Lower is better.
 
Anandtech's Rough Ram Performance Formula:
Frequency/Cas = Performance Index
 
Whichever has a higher performance index is generally faster. If two sets are very close, the higher frequency kit wins.
 
 
Cache Overclocking
 
Cache overclocking is the easiest thing to overclock but has the least impact on performance (comparisons listed in the later sections). By now, everything should already be overclocked and stable except for the cache. Simply set the cache to the same frequency as your core and stress again to check if it's stable. If it's not stable, lower the multiplier by one and repeat. Unlike Haswell, cache can generally get to the same frequency as the core. There isn't even a cache voltage to worry about.
 
 
 
Final Step:
Go back and see if your overclocks still function perfectly with less voltage. How low can you go? This is just fine tuning of your voltages.
 
 
Safe Voltages (TENTATIVE):
Vcore: 1.45v
VCCIO: 1.3v
System Agent (SA): 1.25v
Vdimm: 1.38v
No Cache voltage or Input Voltage with Skylake
 
Quick Word About "24/7 Stability and Safety"
24/7 stability is useful for people using their CPU 24/7. Playing video games a couple of hours a day or week is not the same as hammering your CPU at 100% load for hundreds of hours in a row. If you're really that concerned about CPU longevity you shouldn't be using Prime95 to stress. "100% load 24/7 safety" is a meaningless and vague goal people strive for.
 
Unlike Haswell, Prime v28 and Linpack are no longer much hotter than other tests. They are still the hottest tests around, but it's not quite as ridiculous anymore. For example, Prime v27.9 is similar in temperature to v28.7, As the settings chart notes, I detected temperature fluctuations in Linpack, IBT, and XTU stress even though the load on the CPU still read 100%.
 
Just like in Haswell, note how XTU stress is cooler than XTU bench, and AIDA64 varies in temperature wildly based on the settings checked. Without a way to loop the test, applications like XTU bench and Cinebench are not viable stress tests. As expected, custom x264 at 16 threads is hotter than the 4 thread setting, and using more memory for Linpack causes a hotter test. With the Haswell temperature chart I had 8gb of ram to use, and for this chart here I had 16gb.
 
My temperatures are lower than what most people will observe because I am not running hyperthreading and I am also delidded. 
 
Time to Crash testing is currently WIP. Check back later for more information.
 
 
 
x264 is the recommended and the default go-to stress test for this thread. If you feel the need to use a hotter test that is your right, but know that your overclock may be hampered by that choice. You could forego delidding in many cases simply by switching to x264. The downside to this method is that the overclocking process will take longer because we are replacing a very stressful program and a short test duration with a less stressful one and a longer duration.
 
I highly recommend trying our x264 encoding test if you are looking for a test that can stress while still being pretty cool. For a peace of mind I recommend running x264 looped all night as you sleep once, and if it passes, it's stable. Run it, sleep, wake to see the test still running, pass, smile.
 
Angelotti and JackCY have tweaked the x264 Bench utility and turned it into a stress testing tool. You no longer need to download other programs to get it to work; just download, unzip and run. Simply put, our version of x264 test is better in every way to the original x264 benchmark. There is no reason to use the original utility. There is a readme inside to tell you what options to pick but I will also summarize it here: By default, try the 16 thread setting (yes, even if your CPU is an i5) with normal priority.
 
 
'Prime95 is not Certified for Haswell/Skylake/Insert Nonsense Here'
This was a myth that was perpetuated by some Youtubers. For Skylake it seems this has died down. But know that Prime95 will not eat your CPU and spit out the remains.
 
Prime95:
When you are closer to stability, Prime95 may stop with an error. This is a rounding error, meaning the crash was minor enough so that your computer itself does not crash. There is some data to suggest that Prime95 gives out rounding errors very frequently, even in overclocks considered functionally stable. With Skylake, unlike Haswell, version 28.7 is not significantly hotter than version 27.9. Still, from testing thus far, v28.7 has been shown to crash unstable overclocks faster than 27.9, so consider it a harder test.
 
There isn't conclusive evidence so far about which setting in Prime is the most stressful and prone to crashing unstable overclocks. It is known that smaller FFT sizes tend to cause higher temperatures. 8 is the smallest size (in K, but that's a technicality). It is unknown if using more memory causes unstable overclocks to crash faster.
 
Linpack/IBT
Linpack is a newer version of IBT. Please note that with larger ram usage settings, it will take a while for the memory to be used up and the temperature to increase. This may take 2 minutes or so.
 
 
Below among the list of stress test download links there is a link for "Linpack Package". I have taken Linpack and added Linx GUI to it. You can now use Linpack as Intel originally intended or run the GUI to easily change the test settings.
 

Stress Test Download Links

 

So if I made a program that crashes you at stock clocks, you would feel compelled to underclock your CPU, even if that application in no way represents real-world usage? Passing "all stress tests" really means passing "all stress tests that people happen to have made". If nobody decided to make ultra-mega-Prime95, you would think your overclock is stable. That seems like a random, haphazard way to figuring out if your overclock is stable or not. Computers are built for using, and whether you crash at Prime95, what really matters is whether you crash often enough while using it normally. Forcing yourself to pass a stress test "just in case you use it to its limits" makes no sense either. No point in going down "what ifs" which have no signs of ever happening. And if it does, work it out when it does.

 

 

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linus already made a video on this


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Posted · Original PosterOP

Dat formatting.

Fixed

linus already made a video on this

Yes yes he did, but that was for one processor and didn't really go super in depth into other things besides voltage, multiplier, and an explanation of bclk

Did you just copy and paste? Take out the syntax.

Jesus people how fast do you think formatting happens in a post of this size without breaking things.

Why did you copy/paste this here?

I have tried to point people to this post on the forum when they ask about skylake overclocks but usually get dismissed by the "veterans" on this site that I'm wrong, which ends up with the op following the veterans advice instead of the correct advice.

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Hey,
Nice guide (I first read it on overlock.net, but I don't have an account there :P)

 

After reading this guide and the video of linus I tried some manual overclocking myself.
 

Is this a good overclock?

 

Asus z170 Pro Gaming

i5 6600K

Be Quiet! Dark rock 3

 

45 * 100 MHz

Voltage = 1.3V in bios (first value I tried and looks stable)

Temps during 4th loop of your x264 stresstest with 8 threads:

 

gwuxdzp.png

 

And if I look at this screenshot, the voltage is 1.3, but when I look at CPU-Z it's 1.344V.

How can this be?

AKWRZfZ.png

 

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How bout selecting the whole text and setting the font to Automatic color? Dark theme users will appreciate.


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Hello mattebad.

 

Thank you for spreading the word about my guide. ;)


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nice stats in table as median etc :) Later (in next two weeks) I will add my results.


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Hello mattebad.

 

Thank you for spreading the word about my guide. ;)

 

 

y u post "cache doesn't matter" but u didn't test things that show difference with cache, like XTU? You tested it weird IMO, why not do 4.5 cpu, 4.4 cache/4.3 cache to test, instead of increasing the core speed too?

 

It does show a difference when u tested 4.8/4.8 vs 4.8/3.8, obviously it's not a big difference and it won't help 24/7 use, but for pushing CPU to absolute limits it will help to have as high cache as you can get for them scores!


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y u post "cache doesn't matter" but u didn't test things that show difference with cache, like XTU? You tested it weird IMO, why not do 4.5 cpu, 4.4 cache/4.3 cache to test, instead of increasing the core speed too?

 

It does show a difference when u tested 4.8/4.8 vs 4.8/3.8, obviously it's not a big difference and it won't help 24/7 use, but for pushing CPU to absolute limits it will help to have as high cache as you can get for them scores!

Ok, cache clock matters about <1/10th as much as core clock. It escaped me to test with those things - thought I had the synthetics covered in Haswell section and for Skylake I just did real world testing. So, what real world testing do you want to see done?

 

4.5/4.4 vs 4.5/4.3 would be a waste of time because of margin of error being larger than any legitimate performance loss. It took lowering by 1 ghz to see such small changes in what I tested.

 

My guide is not intended for benchers, and all my advice/safe voltage limits/stress testing sections, all sections do not apply. Such an overclock would not be allowed onto the chart either. If you asked me whether to increase cache for trying to break records, of course I'd say set it to max, every little bit counts. Not so much when you're encoding, archiving like crazy, gaming, etc. Does it "matter" in the latter case? Well yeah, if it makes you feel better in your heart of hearts if it's as high as it can go.

The guide also advises pushing cache to 1:1 for Skylake (and as you know, hard to do on Haswell) in the instructions as well, as an extra. Many people don't follow that step, it's up to them.

 

None of this matters. What matters is what you brought up at the very start: What benchmarks show a difference? What application would a reasonable person do that would see an impact with cache overclocking, and more importantly, aggressive cache overclocking? I'm so burnt out from testing, but I'm seeing now that I may be forced to go back and revisit some things.


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Stop worrying about your audio gear and start jammin' to your favorite tunes already!

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Ok, cache clock matters about <1/10th as much as core clock. It escaped me to test with those things - thought I had the synthetics covered in Haswell section and for Skylake I just did real world testing. So, what real world testing do you want to see done?

 

4.5/4.4 vs 4.5/4.3 would be a waste of time because of margin of error being larger than any legitimate performance loss. It took lowering by 1 ghz to see such small changes in what I tested.

 

My guide is not intended for benchers, and all my advice/safe voltage limits/stress testing sections, all sections do not apply. Such an overclock would not be allowed onto the chart either. If you asked me whether to increase cache for trying to break records, of course I'd say set it to max, every little bit counts. Not so much when you're encoding, archiving like crazy, gaming, etc. Does it "matter" in the latter case? Well yeah, if it makes you feel better in your heart of hearts of it's as high as it can go.

The guide also advises pushing cache to 1:1 for Skylake (and as you know, hard to do on Haswell) in the instructions as well, as an extra. Many people don't follow that step, it's up to them.

 

None of this matters. What matters is what you brought up at the very start: What benchmarks show a difference? Would application would a reasonable person do that would see an impact with cache overclocking, and more importantly, aggressive cache overclocking?

 

 

I feel you doge, XTU shows big difference from what I have seen with cache.  Superpi should show a tiny difference but it's probably like you said, very little percent of improvement.

 

Like I said though, for 24/7 use (which is what your guide is for) cache doesn't make a diff, but for benchers it does :P


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