One hour of OCCT linpack test enough to deem overclock stable?

I overclocked my i7 2600k to 4.5 GHz with 1.37VCore and ran the linpack test in OCCT for one hour, my temps were right around 70C at the hottest core, and the lowest core hovered around 60C, I then played crysis for about 3 hours and my temps never even hit 60 Celcius, the highest core then was right around 58.

Should I go by this 1 hour linpack test? or should I go for a full 8-12 hours of prime95? Frankly- I don't want to spare that much time to test my processor, so I went with the most strenuous test I could find that could test my cpu in the shortest amount of time. After lots of failures and tweaking I finally found a way to get 4.5 GHz and have it pass the test stable.

is Linx any better? I just want to deem my overclock to be rock solid- I pretty much passed the the linpack test in occt for one hour so I honestly think I could deem myself stable, and cool temperature-wise. If I need to do prime95 for 8 or 12 hours, then so be it, I shall do that. :P

Turns out I don't have a brilliant chip either. :( But hey it hit 4.5 GHz and is game stable, i'm definitely not complaining, I could probably squeeze 4.6 or even 4.7 with more voltage but I don't want to induce electromigration. I want this cpu to last long, so I find 1.37-1.38 voltage to be quite fine at this clock. =) I'm honestly quite happy the way I am, but I just want to be stable so my cpu doesn't ehm, kill itself in some un-ordinary fashion.

Cheers!
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More about hour occt linpack test deem overclock stable
  1. 1.37 is very high for a 4.5ghz overclock!!! Try lowering your voltage and follow this guide: http://www.tomshardware.com/forum/274821-29-sandy-bridge-series-overclocking-cores-guide I am able to get my 4.5ghz stable with 1.31v!!
  2. Yeah, I know. :\

    I tried a fixed voltage earlier and it was right around what you were saying and it was rather stable at 4.3 GHz, but when I tried to go for offset voltage- it just was not stable no matter what I did. :\


    I'm just worried about electro migration. :S Would running 1.31 volts for 4.5GHz 24/7 (or even lower if I can pull it off.) damage my cpu in anyway within a few years?

    i'm doing the linpack test again and it's very stable at this fixed voltage and clock. But with offset it would always fail for some reason.

    EDIT: Actually scratch that- it just failed after 7 minutes.

    EDIT: I"m trying a lower memory frequency, but I find that a bit folly considernig I got linpack to be stable with the higher voltage- but non the less I will try running my 2x4 1600MHz sticks at 1333MHz to see if it makes a difference at all in linpack. (Since a lot of memory is tested.) Either something works- or im candidate for the world's worst chip. :D

    EDIT: Well 13 minutes into linpack so far and no fail as of yet. I'll update the post as to what happens in the end.

    EDIT: Blue screened in prime95, that's odd. Upping the voltage to 1.32 to see if it helps, gonna re-run the test.

    EDIT: Gonna try and do 1.30 Volts with this overclock and see if I can get stable with that using variable voltage. Running the linpack test again to quick test, if this comes out of the oven A-ok i'll run prime95 for 8 something hours to make sure im absolutely rock solid.

    EDIT: Well isn't that something one hour of linpack and no errors with my memory running at 1333 MHz and VCore at 1.31 . :lol: I'll do an offset voltage version of this OC since I like to see lower volts- i'll run the linpack test again one more time to ensure that overclock is stable as well. Who knows- maybe I do actually have a magic chip. :ange:

    EDIT: Well I finished the OCCT linpack test for one hour and im stable at 4.5 GHz with 1.30 Volts with offset! :D Should I just use the overclock as it is and call it stable? Or do 8 hours of prime95 to ensure a practical stability? Or maybe even keep lowering my voltage until I no longer pass the linpack test then do prime?

    EDIT: gonna do prime95 for 8 hours. If I pass, then lets just say im rock solid. :D

    EDIT: Im doing prime95 atm, voltage is like 1.31-1.32 (Had to up the voltage because I randomly bluescreened 5 mins into prime95?!?! But no i'm okay for about an hour... so I feel generally safe. =)

    EDIT: Two hours into prime95 with a voltage of around 1.31-1.32 (jumps up and down.) Temps are very reasonable. (below 70 most of the time.) I have confidence that I may pull off 8-10 hours. =)
  3. Less voltage = better for the processor :)

    Keep stability testing!! :D
  4. Well isn't this odd! :D

    I decided to suicide for the fun of it and well...

    I'm currently running 4.7GHz with 1.35 VCore and running a small FFT test im prime95.

    So new goal is 4.7 GHz, i'll do a real test tomorrow with 1.35 VCore, but joy if I get 4.7GHz with just 1.35 Vcore, I think I hold a golden chip after all. :pt1cable:

    Still need to run my memory at 1333MHz, because for some odd reason my i7 doesn't like 1600MHz at anything above 4.5 GHz, not a big loss in gaming at all really, but my encoding times will shoot through the roof! :sol:

    Quick test of 30 minutes shows I may hold a stable voltage of 1.35 volts, but only a true 8 hour test will really tell this, so I will run a large FFT test tonight and test my ram for a short while. And tomorrow I'll attempt to do both tests- both 8 hours straight.

    EDIT: Btw I prefer not to do full 24 hour tests. I won't be folding or anything really. but I'll do a bit more than 8 per test if it's a must...
  5. Do 4 hour runs.
  6. Well, so begins my 4.7 GHz testing, here goes the small FFT's to test for voltage instabilities.

    EDIT: And yup I'll do those four hour tests- afterwards sometime after that though I'll prime95 in blend for 12-16 hours (someday) to ensure stability. =D But if I pass these tests, I can pretty much say im solid for the time being.

    EDIT: Also thanks for the help amuffin. =D I'm growing more and more... attatched here >_> hehe :ange:
  7. Amuffin's advice was good.

    If you don't error in 4 hours on Prime95, you probably won't error. I've been known to run systems that aren't quite stable, because a crash once a week doesn't bother me since I don't do critical work on this system. When gaming I'll usually turn down the overclock because the speed doesn't matter then, and gaming is the one time a crash really bothers me.

    Also, have you tried for higher than 4.7 just to see what the chip can do? To me, that's the most fun part, pushing the chip to its limit, even if you just do it for a day of benchmarking. Going to try to get my 2500k benchmark stable at 5.3 GHz this weekend. Can bench at 5.35 if I turn off two cores, but I'd really like to get there with all four active if this chip can handle it.
  8. I haven't quite tried that yet ^^ As I can not do much more than what my chip is doing at the moment with my corsair a70 . D: But after I find 4.7 GHz and get it stable I'll definitely aim for above 5GHz just to suicide some benchies >:D

    But in other news- I failed the small FFT test- so my chip is of the 'quite not so perfect but still good' kind I suppose? :lol: Running at 1.35 volts with p95 caused a blue screen with a clock interrupt error, so it's indefinitely voltage related. (Well of course it is, it failed the small FFT test! :cry: )

    At any rate, it failed right around 25 minutes in, so now im running with around 1.37 Volts instead (says 1.368 in cpuid) I honestly reckon I may need a tad more to fully pass the test, but lower the better! And this is indeed a step up from my slightly below 1.35 :lol: (infact it's a big step up- but it's a needed step up, blue screens?!?! :( xD)

    Also I want to add that- temperatures even with the increased voltage are still right around 75C for the hottest core under load, the other cores are hovering around 68C and 70C, and these chips can, in a few words, TAKE THE HEAT so to speak, so I'm not worried at all. :sol:

    EDIT: Might want to note that im doing this with hyper threading on... so that's always a killer eventually xD...

    EDIT: PHEWWW Those cores are WORKING, the hottest has come to a stable 77, and the others are literally right around 70, is this safe? I heard these processors can withstand about 90C until throttling. so I feel as if im right on the brink of the 'no-go zone' but nowhere near the 'deadzone' :lol:

    EDIT: Well temperatures haven't changed at all, and im much more stable with this new voltage C: Around 45 minutes into small FFT test and im quite stable so far, I have hope. :D (Although I will not be doing anything as nearly as intense as in this test- I am still thinking of just finding my max reasonable overclock that I can do 24/7, then just backing down to my 4.5 GHz overclock, it was much cooler, right around 70 in prime95, but then again I wont be doing anything crazy except encoding videos and what not. Btw the hottest core hit 79 and is now stable around 78 :heink: Guessing I gotta wait to see my max temperature here. I'm not worried about damage anymore honestly, and I won't be running these temps 24/7 but it would be unhealthy to do so if I needed to. :whistle: )

    EDIT: I'm stable for one hour but this thing is just way to hot an dI shouldve realized that an hour ago when I began the test. :cry: I could run it like this but holy jesus I need to aim for around 75C. Lowering voltage and redoing test around... 1.362 volts

    EDIT: Well this is certainly a bit better... but this is as low as I can go with voltage in this scenario probably. Running p95 small FFT's with 1.36 VCore. my lowest temps are hovering around the upper 60's (68 etc) with the hottest core at 76 to begin with. This will only increase with time- but watcha gonna do? :( Corsair a70 isn't that great of a cooler but it came free with my cpu for 298 dollars so I could not ignore it. :S But at any rate... I'm in the mid 70's and upper 60's so im not worried at all. :) Yet :whistle:

    EDIT: I seem stable first 30 minutes in... Temps are creeping up and down... I reckon I have a fine voltage if I can remain stable per test. Otherwise I'll need to stick with 4.5 GHz it seems. :P I'm not so skilled in ocing, but I am skilled in OCD. :D

    EDIT: This is beginning to seem like a commentary. =D

    EDIT: One hour into the small FFT test once again, and it appears as if im stable for the most part, temps are not exceeding 77C on the hottest core, so im not worried at all! :D I may have a stable overclock, but ill post the results of the test once the entire 4 hour run is done.
  9. Well I just failed the test at 1.36 volts after about 2hours 45 minutes of stress testing, so Im bumping up the voltage and am just going to run occt linpack/w AVX instructions for about 2 hours to get a general idea of where I should be heading here.

    All my fails were this hideous clock stop interrupt blue screen. :S Prime95 doesn't even error, I just blue screen to hell.

    EDIT: oops double post. :c

    EDIT: well the temps aren't as bad as I would have thought them to be so i'll run this for 6 hours just to make sure im rock solid... 6 hours of linpack might be overkill, but it will pretty much tell if I have a stable machine or not. This is bloody murder xD

    EDIT: Well I'm way to unstable at 4.7 GHz, and I will more than likely need a lot of voltage to correct my bsod issues (1.38!!!) , so im clocking back to 4.5 GHz and making sure that in itself is rock solid :) I'll be satisfied. :kaola:

    Maybe I'll invest in some liquid cooling eventually (h100 or a custom solution) and really start overclocking :bounce:
  10. Looks like you know what you're doing. Upper 70s is higher than I'm comfortable with on my chips, but is below the "holy crap you're killing your chip" limit. When benching at 5.2 GHz my chip got all the way up to 85c, but I only ran it that hot for about 20 minutes.

    I actually had the same strategy as you. Was able to run my chip 24/7 at 4.7 GHz (46 x 102), but backed it off to 4.5 for daily use to get temps and voltage down. Every now and then I'll crank the voltage up to close to 1.5v for benching, but not that often. Temps are insane at that voltage, and into the danger zone.
  11. well im one and a half hours into prime95 blend with 4.5 GHz with 1.33 Volts :D I've done linX for 20 passes with this setup once so I know my ram is good with this OC. :bounce: I might just stop at 4 hours and consider it stable! I got my radeon 6950 in the mail and am DYING to try it. :o
  12. Btw my temps with 4.5 GHz 1.33 VCore is about 70C. No more! No less! :D (the highest core hit 71C if that contradicts anything *facepalm* but those temps are good for this OC with a corsair a70) I doubt I'd ever reach 70C except when im encoding, even then i'll be fine. :lol:

    EDIT: Oh my god, double post again, is there a rule against this because as soon as I double post I realize and im all like. :cry:

    EDIT: I passed blend for 2 hours, I reckon i can do over 8 probably with my voltage. I consider myself system stable for the timebeing, just got done with some crysis 2 on my radeon 6950. I love this system. >:D I'll do real 12 hour blend test to make sure im a-okay =D. I'm an advocate of enjoying PC's. So I will enjoy mine for the rest of the night, get up around 4 or 5 AM tomorrow, and do the test till afternoon tomorrow. ^^ If I pass, im solid!


    :lol:
  13. I've never seen any rule about double posting. Don't think anybody cares.
  14. WELLLLL in OTHER news! :D

    I nearly bricked my 6950. I decided to do the bios flash on the 2nd bios my sapphire 6950 2gb supported and lets just say I got a black screen of death. :cry: :cry: :cry:

    But that was easily fixed by just running the first bios I used. :lol: I'll reflash the second bios on the 6950 while using a GTX 550 TI someday. If you fail once, just try again- there's always 2nd chances. :lol:
  15. Well I flashed the bios and to say the least my radeon is back to the way it was when it was shipped to my house.

    What a scare! :wahoo:

    But tomorrow prime95 blend for around 8-12 hours tomorrow to ensure my overclock is stable then im done. :D
  16. shivanthing said:

    Still need to run my memory at 1333MHz, because for some odd reason my i7 doesn't like 1600MHz at anything above 4.5 GHz, not a big loss in gaming at all really, but my encoding times will shoot through the roof!

    You will notice little if any difference at 1600 MHz compared to 1333 MHz.

    Anonymous said:
    I've never seen any rule about double posting. Don't think anybody cares.

    Yes, we do. :)

    John
  17. Ahhhh I'm sorry about that! I will take note of the double posting rule! :D And thanks for the memory tip. ^_^

    But anyway, just woke up around 10 am (was busy de-borking my graphics card's second bios so I woke up late.) I i'll let this run in blend till 6 pm and that will be 8 hours =)
  18. Quote:
    You only need to prime for 1 hour or 2 hours of occt.


    I wouldn't think so if people fail about 8 hours (sometimes more if they keep going) into the test...

    But I will do 8 hours of blend to make sure im rock solid c: :D

    In other news I get this strange light buzz (it variates) from my computer- I'll try to keep the question here so- is it any one of my components within the computer?

    I took the side panel off while my comp was on to see if any wires were getting into fans and lo and behold they were not, I discovered the wires were touching my case though.

    When I pressed on a component (graphics card or cpu cooler) the sound ceased to exist...

    ideas anyone? The sound is gone right now after I did that- and after I re-positioned some wires. It cant be coming from the PSU because it wouldve been constant. Perhaps some wires were just vibrating off the metal? I may tie them together with something to get them to stay off my case. :pt1cable:

    EDIT: I just put my ear to my DVD burner and lo and behold the horror that present itself to us. :cry: It's buzzing :O
  19. Quote:
    When on earth will you stress your CPU as much as these programs do?

    Never..


    The problem with overclocking is that well, a component can fail any time. If I were to stop at one hour it could easily just fail in 2 hours. Which would mean I have a very unstable system.

    It's not really about how long your system can last a certain test, it's more about finding whether you need to bump voltage or modify your memory to fit your overclock. Although doing a lot of stress testing is recommend.

    Doing blend for 8 hours will ensure my computer sorta passes most tests without a hitch- and i'll be generally stable. For folding? No definitely not, you'd need to do a 24 hour test at LEAST to ensure you're stable for folding. But for general use 8 hours of prime in blend is generally ideal for thwarting system errors.

    But that's all in my opinion. :p

    But anyway, still no idea where this noise is coming from, it's obviously a grounding hum issue, I could live with it or track it down like a mad man. :cry:
  20. Quote:
    I had a humming issue with my old Radeon 4870...
    Check your GPU.

    We all test differently for stability.
    I throw in CPU intensive games too (BFBC2/BF3/GTAIV).
    You may pass a test with prime or OCCT, but fail in games.


    Exactly, but prime95 is well, in a word just a 'prime up' so to speak. To see if you're ready to go into the real world!

    And I found my issue, the horror... my motherboard isn' flat on the case. :non: :non: :non: :non: :non: :non:

    Ehhh, 1 hour into prime95, I'll let it go but as soon as I 'pass' (or misrebly fail at 4 hours and put on a poker face) at 8 hours im going to flatten this board so it's flat within the case. :pt1cable:

    EDIT: I can just imagine... if it's anything to do with the brass standoffs then... :cry: I'd need to take my entire board out. :lol:
  21. hmmm... my cpu coltage goes up to 3.7 underload... (2.4 when not) i think i shall lower it a bit...

    sorry it should be 1.37 underload and 1.24 when not (no idea how i manged that...)
  22. o_o what cpu do you have?

    Btw I got rid of the noise, darn screws... (at least it wasnt the brass standoffs :sarcastic: ) I also added some practicle wire control! ;)

    im gonna start prime around 6 tonight and do it nightly instead, I wont be home so I wont need to do anything :bounce:
  23. woah.... 3.7 sorry i meant 1.37 D:

    if you include the bits after the 1.37 in total it was going over the apparent safe voltage by .015

    dropped the vcore in the bios from +150 mv to 100mv it now maxes at 1.33 - 1.34 (i wonder will i see slightly lower temperatures now?)

    Voltage
    CPU CORE 1.328 V
    MEMORY CONTROLLER 1.864 V
    +3.3V 3.408 V
    +5V 5.112 V
    +12V 7.806 V
    VIN5 1.664 V
    VIN6 0.936 V

    is that +12v reading wrong D:? (thats under load from p95 the reading is from speccy) (also i dont know if that memory controler voltage is ok i havent changed the memory controler voltage in the bios at all)

    and its a pentium E6700 3.2ghz overclocked to 3.7 (15% overclock by overclock profile on my motherboard)
  24. Probably, minimal at best. :P All I know is when I had 1.38 for my (very hot yet somewhat stable) 4.7 GHz overclock, my 4.5 GHz overclock with 1.32-1.33 volts is just around 60 Celsius (it hits 70 but doesnt stay there) You probably will see a difference in temperatures, but im not familiar with those CPU's so im not quite sure. :ange:

    EDIT: Uhm not 3.5, 4.5 GHz xD

    Anyway, im turning on prime95 in blend now, gonna leave it running all evening till about 11-12 )7-8 hours. if im stable like that ill just run linx to finalize my ram and I'd say im pretty much stable :D (hopefully I wont cancel the test early, I'll be leaving to go somewhere soon so hopefully all goes well. :P)

    EDIT: NEAR SUCCESS, im into prime95 blend for about 5 hours now!!! Nothing failed! =D Gonna let it run 12 hours and if stable, im rock solid =D

    EDIT: GREAT SUCCESS, 8 hours into prime95 blend and Im still SOLID, I could just stop now and call it stable but I want to make sure im fine for rendering- so im gonna go for 12 hours and make sure this puppoe is solid as GRANITE. :bounce: :bounce: :bounce:

    EDIT: Well I decided against running prime95 in blend for 12 hours, so I stuck with 8 hours and to say the least I passed, so im going to run a different test- linx for about 20 passes to ensure my ram is rock solid as well. (I already did that but I honestly think I should do it again.) Afterwards I think im done stability testing...

    EDIT: ran linx in AVX mode for 25 Passes, took about an hour of testing and pretty much butchered my cpu heat wise (went up to 77 C!!!!!!!!!) But it was stable! That's the great part. I think im done stability testing to say the least. Btw I ran prime95 in blend mode without using all my ram- which is why I did the linpack test with AVX (which used about 86 percent of my ram) for an hour. Am I considered stable or should I redo prime95 in blend with full ram usage tomorrow?
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