I5-2500k/p8z68-v pro Not Overclocking?

I recently built an i5-2500k Sandy Bridge system and have decided that I would like to try overclocking for the first time :o I read the i7-2600k/i5-2500k overclocking guide, disabled all the things that it said (except Spread Spectrum, because I couldn't find it), enabled all the things it said to, and tried adjusting my multiplier. However, when I open CPU-Z and the Asus AI Suite ii, both continue to show my multiplier at x16- although the clock speed will flash to 42-- mhz for a second. Even the AI Suite's automatic overclocking doesn't seem to affect my CPU. I don't know what I am doing wrong. Are there other BIOS settings that I have to tweak? I would be very appreciative if anyone would point me in the right direction.

This is the guide I looked at as a starting point to my overclocking journey:

This is my system:
Intel i5-2500k, cooled by a Cooler Master 212+ EVO (1 fan)
Asus p8z68-v pro motherboard (BIOS v. 8~~~ I don't remember exactly)
g.skill sniper 8gb ram (@1600mhz)
msi lightning GTX 580
PC Power and Cooling Silencer 950w PSU
18 answers Last reply
More about 2500k p8z68 overclocking
  1. Have you disabled speedstep?
  2. The cpu clocks down to 1.6ghz to save power, that is normal and does not affect performance at all. You need to put it under load (like with prime95) to see it go to full speed and to stability test.

    * I would suggest to enable c1e, there's really no point in turning it off unless you're extreme overclocking.
  3. I'm running Prime95 right now and it is showing up with a 42x multiplier and hovering around 51C @1.304V after eleven minutes. Seems like it's doing pretty well to me. Am I correct? Oh, and what is c1e?
  4. At 1.304v you should be at 46 or 47. Are you using offset or fixed? C1e is just another power saving tech. http://en.wikipedia.org/wiki/Advanced_Configuration_and_Power_Interface A couple minutes is fine for fine tuning but I like to run a blend over night when I get to the speed I want. Although others say 1hour is enough, I like to be 100% stable as it needs to be for my rendering.
  5. Offset or fixed?
  6. Vcore mode. Don't tell me you left it on auto. :non:
  7. I don't know...Suppose I did, would I want to set it to offset or fixed?
  8. I just checked the BIOS. Vcore is set to offset (there was no fixed option), but beyond that, it is set to auto. I don't even know what I would adjust it to. Do I have to tweak it in 0.005v increments to find a sweet spot? I also lowered the multiplier to 40x, because I was starting to see temps from 50-54C with Vcore going as high as 1.312 after only a few minutes when I ran prime95 again. :heink:
  9. Auto always puts the vcore too high, like I said 1.304ish is enough for 46ish. Tcase is 72C, ie the safe temp you can go up to. http://ark.intel.com/products/52210

    Change offset to 0 ( I don't think there is 0 so set it to -.005) And change LLC to medium. This should give you 1.3v and change the multi to 46. I might be wrong, every manufacturer has a different offset base value. This is just an easy starting point, you should be able to handle the fine tuning right?
  10. I've never overclocked anything before; my last desktop was actually an Athlon 1100 based machine that my dad built like 9 or so years ago lol. Now that I have at least a starting point, I should be able to figure out the fine-tuning :) I am up for the challenge!
  11. Hi there i just thought id add my thoughts as ive got an i52500k with an asus p8z68-v and I would suggest if you are at 4ghz I would set your vcore to 1.19 /1.20 as mine idles mid twenties and mid 40's in prime9 at 4ghz with cm 212+ at those voltages hope this helps
  12. I just offset Vcore to -0.005v and ran Prime95 for about 70 minutes; Voltage is down to between ~1.26- 1.28 and temps are maxing out at 50C. Thanks for the thought jb. Should I just keep tweaking the offset Vcore value to 1.19/1.2 until I find a spot where it's too low for my system to handle, or should I fix it at 1.19/1.2v and see what happens?
  13. What is your multi? What multi are you aiming for? Did you change llc? What is it set to?
  14. ive heard of people getting atleast 4ghz by setting v core between 1.13 - 1.2 mines at 1.19 at 4ghz but havnt tried dropping the voltages yet but it would drop temps by a few more degrees doing so i will try lowering mine tonight to see what i get as 1.19 was a first attempt and as for vcore offset i havnt changed mine just left it alone
  15. There's not much performance increase after ~4.5ghz worth the extra effort (as you aren't just changing vcore and multi anymore) and it's pretty easy to get there and keep safe temps with a 212+ which is why I suggest to go that high. But even so a stock i5 has plenty of power for a single card setup. I only load my OC profile when I render, otherwise I'm stock since asrock offset base value is 1.3v so I can't overclock lower without having a fixed voltage which is counter productive. Stock vcore is 1.2-1.25 depending on which turbo # of cores. If your reason is power consumption or heat to only go to 1.2v, 1.3v does hit around 30w more and 15C hotter. Set your llc to normal should get you to 1.2v.
  16. I have my load-line calibration set to regular right now. I've offset the Vcore to -0.01v now and I'm running Prime95 as I type this. It's at 1.26-2.8ish volts right now. Should I just keep offsetting it until I get lower voltages?
  17. You mean lowering the offset til it's unstable, yes.
  18. I have the same processor and heatsink, mobo is extreme3 gen3 asrock. I set mine at 4ghz, with offset at -.05. didnt wana go any lower cuz its at 1.2 at load, and .9 at idle which i'm fine with.
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