Solved

Will setting uncore far below core clock cause any future issues?

i5 6600k: uncore x35, core x43. Any issues this might cause?
7 answers Last reply Best Answer
More about setting uncore core clock future issues
  1. Best answer
    It wont cause any issues, uncore has low impact on performance. You can leave it stock which is 35. However it wont hurt if you rise it a bit for example to 39-40 either. I personally keep it 300-400mhz down from core clock.
  2. Thanks. Apologies for the delay in selecting the solution.
  3. Makentox said:
    It wont cause any issues, uncore has low impact on performance. You can leave it stock which is 35. However it wont hurt if you rise it a bit for example to 39-40 either. I personally keep it 300-400mhz down from core clock.


    Ideally the Uncore ratio should be the same as the core ratio (as it is at stock values) or (particularly in the case of overclocking) higher than the clock ratio to not constitute a bottleneck. On my Intel i5 6600K I set the Core at 46 (4.6 GHz) and the Uncore at 49 (4.9 GHz) - yes, much higher than the Core! I tested it stable on a 2H Prime95 Blend test up to Uncore 52 and could probably go beyond that value but the overall performance drops after 49, so that's what I use.
    To measure performance I measure the time it takes for the system to complete the Prime95 800K test on the four workers. Setting the Uncore ratio at 49 rather than 40 shortens the time by some 7 minutes (from 48 min. to 41 min.). Getting 7 minutes shaved off on 48 is getting 14.5% of raw processing (computational) performance gain! It does not change the Temp. and Power significantly from 40 to 49 (topping at 84 C max under 26 C ambient and 104.5 W) although I had to up VCore from 1.355 V to 1.390 V to ensure stability. The stability of the PC (BSODs, hanging, etc.) is also much greater, in fact rock solid (never had any trouble ever since). It is so good that I really feel it.
    Games that would usually get the 4 cores at (for example) 98-96-100-97%, now leave them at 83-87-93-84%, further showing the overall gain in CPU performance. THIS IS ABSOLUTELY FANTASTIC !!!
  4. Cache frequency has very little impact on CPU performance, but can have a noticeable effect at higher memory frequencies by improving latency results. This why it took less time in prime. However fps gain in games is 0. Ive never heard someone setting uncore above core. It usually brings instability when i set it to = core and sadly 0 perfomance gain for my everyday tasks. Also do u get your magic boost in all games or which? What ur ram mhz/timing? Your system spec?
  5. Makentox said:
    Cache frequency has very little impact on CPU performance, but can have a noticeable effect at higher memory frequencies by improving latency results. This why it took less time in prime. However fps gain in games is 0. Ive never heard someone setting uncore above core. It usually brings instability when i set it to = core and sadly 0 perfomance gain for my everyday tasks. Also do u get your magic boost in all games or which? What ur ram mhz/timing? Your system spec?


    I have been running my 6600K for 18 months at 4.6 GHz after manually setting VCore at 1.380 V in the BIOS. With this, I set the Uncore Ratio (cache) to "49" (or 4.9 GHz) - yes, much higher than the Core ratio! It is mighty stable under anything Prime95 can throw at it and for as long as I want...

    Here are details of my current, and ultra stable/safe, BIOS settings for i5 6600K on Gigabyte GA-Z170XP-SLI with 16 GB of RAM (4 x 4):
    [1] - CPU Core Ratio: 46
    [2] - FCLK Frequency For Early Power: 1 GHz
    [3] - Uncore Ratio: 49
    [4] - CPU Flex Override: Disabled
    [5] - Intel Turbo Boost Technology: Disabled
    [6] - CPU Enhanced Halt (C1E): Disabled
    [7] - C6/C7 State Support: Disabled
    [8] - C8 State Support: Disabled
    [9] - CPU Thermal Monitor: Enabled
    [10]-CPU EIST Function: Enabled
    [11]-Voltage Optimization: Enabled
    [12]-Residency State Registration (RSR): Disabled
    [13]-Hardware Prefetcher: Enabled
    [14]-Adjacent Cache Line Prefetch: Enabled
    [15]-Extreme Memory Profile (X.M.P.): Profile 1
    [16]-System Memory Multiplier: 32
    [17]-Memory Enhancement Settings: Relax OC
    [18]-Channel Interleaving: Enabled
    [19]-Rank Interleaving: Enabled
    [20]-CAS Latency: 15
    [21]-tRCD: 17
    [22]-tRP: 17
    [23]-tRAS: 28
    [24]-Command Rate (tCMD): 1
    [25]-CPU VCore Loadline Calibration (LLC): High
    [26]-CPU VCore: 1.380V
    [27]-CPU VCCIO: Auto
    [28]-CPU System Agent Voltage: Auto
    [29]-PCH Core: Auto
    [30]-DRAM Voltage (CH A/B): 1.360 V
    [31]-Internal Graphics: Disabled

    Now then, let's address your comments:
    <<Cache frequency has very little impact on CPU performance>> true for values below the Core freq. since the Uncore remains just a bottleneck for the CPU. But once you get true stability with a suitable VCore (1.380 V in my case) at Core/Uncore parity, e.g. 46/46, then increasing the Uncore freq. will start having a great impact on CPU performance (I get 14.5 % !!!) and without affecting stability. Stop increasing Uncore once you detect that you have reached the peak (even go back a little if required). Again, you detect that by measuring the time the PC takes to perform the exact same run (test), like the Prime95 "In-Place large FFTs test", in the exact same conditions. And repeat the measurements to be absolutely sure...

    <<a noticeable effect at higher memory frequencies by improving latency results>> no, NOT "noticeable", just fractions of a single percentage point, particularly once you already have memory at 3200 MHz. Beyond that it becomes nil.

    <<This why it took less time in prime.>> I also used the Prime95 "In-Place large FFTs test" to measure how long the system takes to complete the 128 K test on the four workers (around 8 min. 38 sec. with Uncore 49). This test uses very little memory (they say "some RAM tested"). UnCore 50 took 8 min. 39 sec., and UnCore 51 was taking 8 min. 59 sec. indicating that the peak had already been reached.

    <<Ive never heard someone setting uncore above core.>> well, now you have. Try it yourself rather than following the herd mentality. You can only get the immense performance gains that I am getting.

    <<It usually brings instability>> yes, and I had a BSOD with Uncore 47, Core 46 and VCore 1.370. BUT once I found the stable VCore of 1.380 V, my system has become more stable than it has ever been. I now throw anything at it and it never fails.

    <<sadly 0 perfomance gain for my everyday tasks>> that's why it's time for you to change and go the other way, way over the Core value. I use my 14.5 % performance gain in my everyday tasks with great benefits, because this is "real" computational performance, not some rendering/fps gain in some game. By the way, I get in all the games because I play them with my two GTX 970 cards mounted in SLI which requires a fair bit of additional CPU work. Once again, this is not some specific game rendering gimmick (polygon count...) , this is real processing performance at the PC level by no longer having the Uncore as a bottleneck to its CPU but really assisting the CPU.

    In the BIOS of my Gigabyte GA-Z170XP-SLI motherboard, when I click on "Uncore" it indicates something like: "In overclocking configurations, it is better to set the Uncore ratio at or above the Core ratio". I really can't take a picture now because I would have to reboot and go into the BIOS of course. I will try that the next time I reboot to show you. The Gigabyte engineers are not completely stupid IMO and surely would be careful when printing such a widely distributed statement to prevent being taken for ignorant fools. Admittedly I too was surprised when reading it at first because it goes against the herd mentality. But then I thought "what if"? What if these guys were not complete idiots. And so I tried from parity (46/46) and kept increasing the Uncore ratio while measuring at every new value the time my PC took to accomplish the exact same test run (and more than once each time). From Uncore 46, then 47, then 48 I had already shaved off over 6 minutes on a total of 48 minutes. At Uncore 49 I was 7 minutes faster than my baseline which is the same test performed in exactly the same conditions (except that the ambient temperature was 0.3 degree Centigrade lower) at an Uncore ratio of 38 (46/38). I had the Uncore at 38 with the Core at 46 to allow me to run at VCore 1.345 V fully stable. I was also running at 46/38 under VCore 1.335 V but then only partially stable (30 min. of Prime95 Blend test before one worker started to fail).

    Besides, when now running the Prime95 Blend test for a long period of time, my max Temp periodically reaches 86 C for a few seconds (at over 26 C ambient) and the power tops at 104.50 W. My CPU fan goes up to 1745 RPM Max. for a very short while. Most of the time, my Temp. stays under 70 C, even now at 27.2 C ambient. Let us remember that the Temp values are standard at 22 C ambient. So at 86 C with 26 C ambient, I am still way under 85 C with 22 C ambient which is fine. My CPU fan (SYS 1) is designed to go up to 2000 RPM, so it still has enough left over (I have seen it reach 1989 RPMs when testing on 4.7 GHz - too high).

    This is a true 14.5 % performance gain on real (practical) "PC runtime", not some fictitious fractions of percentages over a colourful graph from TweakTown. However, it is not for me to take all the credit. I really thank the Gigabyte engineers and/or designers for having placed that little note as a help for overclockers in the BIOS... and will try to publish a picture of it from my screen. I looked in the printed/online doc. but can't see any mention of it (not surprised, many other things from the BIOS are missing from the doc).

    So please, look into this and try it thoroughly, it is really worth the effort... would it be just to make sure.

    OK, I just got the camera out, rebooted, and took the following pictures:
    (Note also my 46 and 49 ratios)








    And here is a new Prime95 Blend test result from CPUID HWMonitor of 41 minutes that I ran under a slightly higher ambient temp. (up to and including the completion of the 800K of the Blend test for the 4 workers):


    Note: On the last pic I indicate with my finger the word "higher" in case it were missed (this is the most important word in this text after all). This one replaces a previous pic showing my middle (longest) finger and parts of my hand, but pointing up that way could have been misconstrued ;-).

    So here it is, you have the exact wording. Nowhere does it even suggest that it should be anything LOWER than the Core ratio. Yet almost everybody has it around 400 MHz lower (?). Why? ... fashionable he... well, all MISGUIDED guys. Besides, when it mentions "Note: In overclocked configurations it is recommended to set the Uncore ratio equal to or higher than CPU clock ratio.", it doesn't indicate by how much it is recommended to set it HIGHER. I went all the way from parity 46/46 (that's the "equal" part) to 46/49 (that's the "higher" part) and stopped there before performance starts dropping. Et voila!

    As I wrote above, are these Gigabyte guys completely bonkers then? Hmmm... didn't think so. But maybe it's just me.
  6. Makentox said:
    Cache frequency has very little impact on CPU performance, but can have a noticeable effect at higher memory frequencies by improving latency results. This why it took less time in prime. However fps gain in games is 0. Ive never heard someone setting uncore above core. It usually brings instability when i set it to = core and sadly 0 perfomance gain for my everyday tasks. Also do u get your magic boost in all games or which? What ur ram mhz/timing? Your system spec?


    I know I read this somewhere:
    <<Cache frequency has very little impact on CPU performance, but can have a noticeable effect at higher memory frequencies by improving latency results.>>

    Here, on TweakTown, I was right:
    Take Away: Cache frequency has very little impact on CPU performance, but can have a noticeable effect at higher memory frequencies by improving latency results.

    Please, let's not repeat (Copy/Paste) "Blindly" what other people plaster all over the internet. Do your OWN tests, come up with your OWN conclusions... and in the process, prove the herd mentality wrong. People also stupidly believed in the powers of the sun, the stars, etc. until one day, the Messiah delivered His message... and changed everything.

    Read more: https://www.tweaktown.com/guides/7481/tweaktowns-ultimate-intel-skylake-overclocking-guide/index4.html
  7. philipew said:
    Makentox said:
    Cache frequency has very little impact on CPU performance, but can have a noticeable effect at higher memory frequencies by improving latency results. This why it took less time in prime. However fps gain in games is 0. Ive never heard someone setting uncore above core. It usually brings instability when i set it to = core and sadly 0 perfomance gain for my everyday tasks. Also do u get your magic boost in all games or which? What ur ram mhz/timing? Your system spec?


    I have been running my 6600K for 18 months at 4.6 GHz after manually setting VCore at 1.380 V in the BIOS. With this, I set the Uncore Ratio (cache) to "49" (or 4.9 GHz) - yes, much higher than the Core ratio! It is mighty stable under anything Prime95 can throw at it and for as long as I want...

    Here are details of my current, and ultra stable/safe, BIOS settings for i5 6600K on Gigabyte GA-Z170XP-SLI with 16 GB of RAM (4 x 4):
    [1] - CPU Core Ratio: 46
    [2] - FCLK Frequency For Early Power: 1 GHz
    [3] - Uncore Ratio: 49
    [4] - CPU Flex Override: Disabled
    [5] - Intel Turbo Boost Technology: Disabled
    [6] - CPU Enhanced Halt (C1E): Disabled
    [7] - C6/C7 State Support: Disabled
    [8] - C8 State Support: Disabled
    [9] - CPU Thermal Monitor: Enabled
    [10]-CPU EIST Function: Enabled
    [11]-Voltage Optimization: Enabled
    [12]-Residency State Registration (RSR): Disabled
    [13]-Hardware Prefetcher: Enabled
    [14]-Adjacent Cache Line Prefetch: Enabled
    [15]-Extreme Memory Profile (X.M.P.): Profile 1
    [16]-System Memory Multiplier: 32
    [17]-Memory Enhancement Settings: Relax OC
    [18]-Channel Interleaving: Enabled
    [19]-Rank Interleaving: Enabled
    [20]-CAS Latency: 15
    [21]-tRCD: 17
    [22]-tRP: 17
    [23]-tRAS: 28
    [24]-Command Rate (tCMD): 1
    [25]-CPU VCore Loadline Calibration (LLC): High
    [26]-CPU VCore: 1.380V
    [27]-CPU VCCIO: Auto
    [28]-CPU System Agent Voltage: Auto
    [29]-PCH Core: Auto
    [30]-DRAM Voltage (CH A/B): 1.360 V
    [31]-Internal Graphics: Disabled

    Now then, let's address your comments:
    <<Cache frequency has very little impact on CPU performance>> true for values below the Core freq. since the Uncore remains just a bottleneck for the CPU. But once you get true stability with a suitable VCore (1.380 V in my case) at Core/Uncore parity, e.g. 46/46, then increasing the Uncore freq. will start having a great impact on CPU performance (I get 14.5 % !!!) and without affecting stability. Stop increasing Uncore once you detect that you have reached the peak (even go back a little if required). Again, you detect that by measuring the time the PC takes to perform the exact same run (test), like the Prime95 "In-Place large FFTs test", in the exact same conditions. And repeat the measurements to be absolutely sure...

    <<a noticeable effect at higher memory frequencies by improving latency results>> no, NOT "noticeable", just fractions of a single percentage point, particularly once you already have memory at 3200 MHz. Beyond that it becomes nil.

    <<This why it took less time in prime.>> I also used the Prime95 "In-Place large FFTs test" to measure how long the system takes to complete the 128 K test on the four workers (around 8 min. 38 sec. with Uncore 49). This test uses very little memory (they say "some RAM tested"). UnCore 50 took 8 min. 39 sec., and UnCore 51 was taking 8 min. 59 sec. indicating that the peak had already been reached.

    <<Ive never heard someone setting uncore above core.>> well, now you have. Try it yourself rather than following the herd mentality. You can only get the immense performance gains that I am getting.

    <<It usually brings instability>> yes, and I had a BSOD with Uncore 47, Core 46 and VCore 1.370. BUT once I found the stable VCore of 1.380 V, my system has become more stable than it has ever been. I now throw anything at it and it never fails.

    <<sadly 0 perfomance gain for my everyday tasks>> that's why it's time for you to change and go the other way, way over the Core value. I use my 14.5 % performance gain in my everyday tasks with great benefits, because this is "real" computational performance, not some rendering/fps gain in some game. By the way, I get in all the games because I play them with my two GTX 970 cards mounted in SLI which requires a fair bit of additional CPU work. Once again, this is not some specific game rendering gimmick (polygon count...) , this is real processing performance at the PC level by no longer having the Uncore as a bottleneck to its CPU but really assisting the CPU.

    In the BIOS of my Gigabyte GA-Z170XP-SLI motherboard, when I click on "Uncore" it indicates something like: "In overclocking configurations, it is better to set the Uncore ratio at or above the Core ratio". I really can't take a picture now because I would have to reboot and go into the BIOS of course. I will try that the next time I reboot to show you. The Gigabyte engineers are not completely stupid IMO and surely would be careful when printing such a widely distributed statement to prevent being taken for ignorant fools. Admittedly I too was surprised when reading it at first because it goes against the herd mentality. But then I thought "what if"? What if these guys were not complete idiots. And so I tried from parity (46/46) and kept increasing the Uncore ratio while measuring at every new value the time my PC took to accomplish the exact same test run (and more than once each time). From Uncore 46, then 47, then 48 I had already shaved off over 6 minutes on a total of 48 minutes. At Uncore 49 I was 7 minutes faster than my baseline which is the same test performed in exactly the same conditions (except that the ambient temperature was 0.3 degree Centigrade lower) at an Uncore ratio of 38 (46/38). I had the Uncore at 38 with the Core at 46 to allow me to run at VCore 1.345 V fully stable. I was also running at 46/38 under VCore 1.335 V but then only partially stable (30 min. of Prime95 Blend test before one worker started to fail).

    Besides, when now running the Prime95 Blend test for a long period of time, my max Temp periodically reaches 86 C for a few seconds (at over 26 C ambient) and the power tops at 104.50 W. My CPU fan goes up to 1745 RPM Max. for a very short while. Most of the time, my Temp. stays under 70 C, even now at 27.2 C ambient. Let us remember that the Temp values are standard at 22 C ambient. So at 86 C with 26 C ambient, I am still way under 85 C with 22 C ambient which is fine. My CPU fan (SYS 1) is designed to go up to 2000 RPM, so it still has enough left over (I have seen it reach 1989 RPMs when testing on 4.7 GHz - too high).

    This is a true 14.5 % performance gain on real (practical) "PC runtime", not some fictitious fractions of percentages over a colourful graph from TweakTown. However, it is not for me to take all the credit. I really thank the Gigabyte engineers and/or designers for having placed that little note as a help for overclockers in the BIOS... and will try to publish a picture of it from my screen. I looked in the printed/online doc. but can't see any mention of it (not surprised, many other things from the BIOS are missing from the doc).

    So please, look into this and try it thoroughly, it is really worth the effort... would it be just to make sure.

    OK, I just got the camera out, rebooted, and took the following pictures:
    (Note also my 46 and 49 ratios)








    And here is a new Prime95 Blend test result from CPUID HWMonitor of 41 minutes that I ran under a slightly higher ambient temp. (up to and including the completion of the 800K of the Blend test for the 4 workers):


    Note: On the last pic I indicate with my finger the word "higher" in case it were missed (this is the most important word in this text after all). This one replaces a previous pic showing my middle (longest) finger and parts of my hand, but pointing up that way could have been misconstrued ;-).

    So here it is, you have the exact wording. Nowhere does it even suggest that it should be anything LOWER than the Core ratio. Yet almost everybody has it around 400 MHz lower (?). Why? ... fashionable he... well, all MISGUIDED guys. Besides, when it mentions "Note: In overclocked configurations it is recommended to set the Uncore ratio equal to or higher than CPU clock ratio.", it doesn't indicate by how much it is recommended to set it HIGHER. I went all the way from parity 46/46 (that's the "equal" part) to 46/49 (that's the "higher" part) and stopped there before performance starts dropping. Et voila!

    As I wrote above, are these Gigabyte guys completely bonkers then? Hmmm... didn't think so. But maybe it's just me.


    I can confirm what this guy is saying to be true.

    Although i haven't done any thorough testing myself, i can safely say Increasing the Uncore Ratio, has given me a noticable improvement in video-games.

    I am not talking about giving me fore FPS, however, i am taking about giving me a noticable reduced latency in demanding CPU games, like Rainbow Six Siege, PUBG.

    I can finally aim properly! Just by increasing my Uncore Ratio. I always felt there was this little noticable input lag, when moving around my mouse, simillar to the effect Vsync causes, but not as noticeable.

    Then I increased my Uncore Ratio, like my Gigabyte Z170x Gaming Mobo suggested in OC configurations and i could tell the results.

    I prefer having a @4.4Ghz + Higher Uncore or @4.5Ghz OC + Higher Uncore rather than going for a @4.6GHz OC + stock Uncore.

    Games just feel way better. P.S. I am also using 3000MHz DDR4 16GB(2x8) RAM at 15-17-17-35 (stock XMP settings)

    1 Thing i will complain however, is the fact that my RAM won't work in dual channel mode in this MOBO: Z170x gaming 3

    I can only get my system to boot, if i put em on these slots: 4&3 and if there isn't any ram at slot 4, the machine won't boot at all...

    I RMA'ed my MOBO, i changed my RAM Kit, i changed my PSU and this issue is not resolved. The MOBO is faulty from production worldwide, as i am having other simillar issues to that all around with my PC, such as input lag introduced from it's internal sound processor/network card. I tried fixxing my drivers, but this latency wont get fixxed, it's constantly at 1000μs.
Ask a new question

Read More

Overclocking Core Intel i5