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My E8400 overclocking journey - what's the limit of this processor?

Discussion in 'Overclocking & Cooling' started by Black Panther, Dec 14, 2008.

  1. Black Panther

    Black Panther Senior Moderator™ Staff Member

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    So I commenced overclocking.
    3.2Ghz - no issues
    3.4Ghz - no issues
    [​IMG]

    3.6Ghz - no issues either.
    [​IMG]

    As you can see, temps are great.

    However, when I was at 3.6Ghz and went to the bios to put the FSB at 401 - I found that somehow the cpu voltage had been set to 'auto'.
    And it said 'auto' in yellow (all other bios fonts are white on blue background). It was supposed to be at 1.2V because that's how I had put it.:eek:
    What's more, I didn't have the option to change it from auto!
    I rebooted a couple of times to check if I was missing something... in vain.
    The only way I could get back the voltage choices to show was to revert to 3.4Ghz, reboot into Windows, restart pc and enter bios again.

    Notwithstanding this stubborn 'auto' voltage glitch, I decided to try for 3.8Ghz.
    I put the vcore on 1.2V again... and.... booted to Vista with no problem at all at 3.8Ghz.
    But OMFG the temperatures!!! I was idling at 51 degrees... and just 12 seconds Orthos got me 64 degrees on RealTemp and 68 degrees on CoreTemp! I quitted Orthos after 12 seconds because I really didn't want to see what maximum temperatures I got... :wtf:
    [​IMG]

    So I got basically 2 questions --

    1) Is there a way I can prevent the bios from automatically changing the vcore I choose to 'auto'?

    2) What is the reason that at 3.6Ghz I get awesome temperatures but at slightly more 3.8Ghz I get awful temperatures?
    (My vcore got changed to "auto" both at 3.6Ghz and 3.8Ghz.

    Thanks! :respect:
  2. p_o_s_pc

    p_o_s_pc F@H&WCG addict

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    it could be the sensor or maybe the Vcore got upped more from 3.6-3.8
    Crunching for Team TPU
  3. Black Panther

    Black Panther Senior Moderator™ Staff Member

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    I forgot to take cpu-z screenies.
    Right now I'm at 3.6Ghz - cpu voltage has been put on auto by my bios automatically...
    Note how notwithstanding this, CoreTemp above still reports the voltage to be 1.2V
    However I just checked out with CPU-Z and at 100% load my voltage is only 1.112V :confused:
  4. DOM

    DOM

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    :roll: coretemp doesnt read the v-core like cpu-z ;)

    its the vid on the cpu

    what the volts at 3.8 in cpu-z
  5. p_o_s_pc

    p_o_s_pc F@H&WCG addict

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    beat me too it :laugh:

    also anyway in the BIOS that you can set your own voltage?
    Crunching for Team TPU
  6. Black Panther

    Black Panther Senior Moderator™ Staff Member

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    Lol, ok - I just downloaded the latest version of coretemp and I hadn't realised that. The previous version I had didn't measure VID and I thought the reading on the new one was vcore!

    p_o_s_pc -Every time I put the vcore at 1.2 (coincidentally the same as the vid reported in coretemp!) in the BIOS. Even when I oc'd to 3.8Ghz I had put 1.2V in the BIOS - but when I go back to the bios I find that the vcore is set "Auto" in bright yellow fonts and it isn't possible for me to change it unless I downclock to 3.4Ghz.
  7. DOM

    DOM

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    your on the latest bios right ?
  8. p_o_s_pc

    p_o_s_pc F@H&WCG addict

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    i have no idea on what you could do then..
    Crunching for Team TPU
  9. Black Panther

    Black Panther Senior Moderator™ Staff Member

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    Yup. I had to in order to upgrade from E4300 to E8400.

    I just oc'd back up to 3.8Ghz, checked cpu-z and got a fright.
    The vcore read 1.44V :eek:
    (The safe maximum of the E8400 is 1.3625)

    So, apart from getting only the "Auto" choice in the bios if I go over 3.4Ghz, my cpu-z vcore reading is 1.44V if I'm at 3.8Ghz, yet the same 'auto' setting gives me a very safe 1.152V if I'm at 3.6Ghz.

    (Gotta be careful or I'm gonna fry something... darnd motherboard...):banghead:

    --------------------

    Edit: I'm thinking that maybe the bios voltage is freaking out because I'm giving it a too low voltage for the oc in the first place - 1.2V.

    I'll try manually setting the voltage at a safer 1.3V, oc to 3.7Ghz and see what happens.

    If my bios will still freak out and put the vcore on auto.... I'll think I'll give up :ohwell: pity for an E0 E8400... :(
    Last edited: Dec 14, 2008
  10. Black Panther

    Black Panther Senior Moderator™ Staff Member

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    Problem solved.....


    YAY I MADE IT TO 4.0GHz!!!!!!!!!11111!!!1111 :rockout:


    The issue with the bios voltage was just as I suspected (see edit in my previous post), apparently when the bios saw that 1.2V was too little for a 3.8Ghz OC, it freaked out and "auto-ed" it to around 1.5V (hence me getting 1.44 vcore in cpu-z). Pretty unintelligent bios... over-volting my cpu to a dangerous region... :shadedshu

    Here's the screenshot (corespeed is 2.5Ghz because multi is x6 not x9 due to speedstep - when I saw those volts I just rebooted, didn't run orthos...):
    [​IMG]


    So I thought of increasing the bios vcore to 1.3V (anything below 1.3625 is safe for an E8400) and overclock to 3.7Ghz.
    Screenshot below shows a respectable voltage and respectable temperatures:
    [​IMG]

    Then I increased the bios vcore to 1.35V and oc'd to 3.8Ghz ----
    [​IMG]


    Finally I kept the bios vcore at 1.35V and oc'd to 4.0Ghz ----
    [​IMG]
    :toast::rockout::toast::rockout::toast::rockout: :toast:

    Incidentally, no matter what clock the cpu is running at, if I enter the BIOS, even now, I'd find vcore saying "auto" in bright yellow.
    However apparently it goes into 'crazy auto mode' only if I change the FSB higher without first changing it lower in order to get the actual choices of vcore and not just 'auto'.

    I'm guessing that if cpu-z keeps quoting me a decent voltage below 1.35V I'm safe and my processor's safe.

    ---------------

    Edit: I think I found the sweet spot voltage for 4.0Ghz to give me the best temperatures for that clock -- here's 4.0Ghz at 1.30Vcore in BIOS:

    [​IMG]

    Now off for some stability testing, game testing, and benchmarking...
    Last edited: Dec 14, 2008
  11. SK-1

    SK-1

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    Congratulations;) I new member to the 4Ghz. Club. I believe you are very safe @that voltage.
    Black Panther says thanks.
  12. DOM

    DOM

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    you need to save youe settings in the bios in one of the porfiles its the samething that happens to me on my mobo when you reboot to the bios if its in auto (yellow) if you reboot again it well let you selet the volts

    but i save it to the profile then load it so i dont have to reboot a 2nd time iv asked on asus fourms no help :( its cuz of the E0
    Black Panther says thanks.
  13. gunner93 New Member

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    hows did you overclock it i tried it a lot but was not successful

    i would be thankful to you if you let me know how you did it
  14. Black Panther

    Black Panther Senior Moderator™ Staff Member

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    Update --

    So I had tried up till 445 FSB and stopped. Some pm'd me asking me some oc details however I didn't really have the time to play around oc'ing during the week since I planned to oc this weekend.

    So come this Friday, I set out to try a little bit more.......

    [​IMG]

    :eek:

    [​IMG]

    I must say it isn't that bad... on air!
    I admit I haven't stability-tested so far. I did play Fallout3 for an hour and a half and it didn't crash or anything though.

    On Intel Burn Test (Linpack) I got 67 degrees after 20 minutes though. It was still stable but I quit it because of the temperatures. Would you suggest that I continue the benchmark or maybe try to lower the NB and other voltages because the temps could get dangerous?
    Well anyway please bear with me now, all I can think of is omgwow11!!11omg I got a 4.2Ghz processor running quite stable! :eek:
    Last edited: Dec 19, 2008
  15. DOM

    DOM

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    you got a nice cou there ;)

    why dont you try how high the fsb goes up drop the multi to X6 mine goes to 580 MAX with not that much NB 1.55 v and fsb at 1.3v

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