Hi guys I am really hoping someone can help me. I am trying to overclock my 4820k on the EVGA X79 Dark. I am trying to overclock using the standard 100Mhz CPU strap and adjusting the multiplier. Whenever I change the multiplier to anything over 37 it will not stay when I boot into windows. In the BIOS it will say I am overclocked 4.5, etc.. but when I boot into windows it will stay at 37 (3.7Ghz) no matter what I do. I have checked in CPU-z, and I also have real temp start with windows and both report 3.7Ghz even though in the BIOS I am at 4.5Ghz. What is really strange is that when real temp first starts it says 4500MHZ for about half a second and then reverts to 3700Mhz. I have speedstep disabled, and loading the CPU doesn't change anything, it still stays at 3.7.
 
I can overclock using the 125Mhz CPU strap because if the multiplier stays under 37 then it overclocks just fine. But I really want to use the 100Mhz strap so I have better options for my RAM frequency and then I would not be limited to only 4.5Ghz or 4.625Ghz.
 
There has to be a setting I am missing. Has anyone else had this issue?
 
For example, do I want to have turbo mode enabled or not? It actually doesn't seem to matter because I get the same result either way, but I am unsure if there is some combination of settings that will allow multiplier adjustment above 37.
 
Or can someone point me to an overclocking guide for this board so I can at least see the settings I need to use? I understand how to make vcore adjustments, I just need to find out what setting I am missing that will allow a multi over 37.

If you look at CPU-Z's "multiplier" block, you'll see that it goes from 12 to 45. 45 multiplier  X 100 strap = 4.5 GHz. Windows IS seeing it, but looks like it isn't ramping up.
 
Try putting a load on the CPU, like Intel Burn Test, or Prime95, and check CPU-Z and Core Temp again.
 
 

MhzManiac
I run 4.75G a little different; 38x 125 but some things should be the same between us. You should leave your C states to default. Let the CPU rest when it can, use a benchmark like the one in real temps to throttle it up. If it won't boot, probably not enough juice to the CPU.  EIST should be enabled. Set OCP to 125%. Hope this helps.

+1.
 
OCP setting can be left on "Auto".

It sounds like the CPU has a partial lock like my Sandy but I can get that to take to low 40's if Turbo is enabled. I wonder if your CPU isn't responding to turbo? 

Out of curiosity, can you run Prime95 or Intel Burn Test with just 1 thread and see what you get? At stock, your CPU should boost one core to 3.9GHz. If it can't do that and if you are within your return window then RMA that sucker as not working as described.

I ended up buying an ASUS Rampage IV Extreme as well. I pretty much already knew the board wasn't to blame, but I got it really cheap so I thought I'd try it out. Well.. I am getting the same results with this board. The multi still won't register over 37. So it really is something I am missing in the BIOS or I have a bad chip. I seems like it would be the chip, but I have been able to find other posts on other forums when searching google referring to the same problem, so unless it's a problem with a lot of 4820ks out there, then I must be doing something wrong.
 
But the good news is the the RIVE is for some reason giving me a better OC on my RAM, so I am able to run it a frequency I am happy with as opposed to what I was getting out of the Dark. So using the 125Mhz strap isn't hindering me anymore with the new board. It's  rated for 1866 CL9 and on the EVGA Dark I had to either bump the voltage to 1.55v to get it to run at those timings or I had to drop it to 10-10-10. But now with the RIVE not only can I run them at 9-9-9-24 with 1.5v, I can also do 2000Mhz at 11-11-11-30 with 1.5v. I don't know why the board would matter for this but it does. CPU overclock is the same on either board. I can do 4.625 using the 125Mhz strap using the same voltage on either board. But the RAM overclocks much better. I'm happy to get 2000Mhz out of these sticks, and RAM frequency was my concern to begin with. So If I can't figure out the problem, or I just have a messed up chip, its all good anyway, because I can now run 4.625Mhz with 2000Mhz RAM.
 
Thanks so much for the replies guys. If anyone ends up being able to point out the answer I'd love to know it if there is one.
 

arestavo

Out of curiosity, can you run Prime95 or Intel Burn Test with just 1 thread and see what you get? At stock, your CPU should boost one core to 3.9GHz. If it can't do that and if you are within your return window then RMA that sucker as not working as described.

How do I disable cores/threads like that? I've never done it before. Also the CPU was used, so I have no warranty.

bdary

Hmm, did you change any settings in the Windows Power Options that may be limiting the CPU's full potential?  Verify that your CPU can use up to 100%.

Yes I am on High Performance settings. No problem there. And when loaded the CPU is definitely at 100%.