Help stability of 2500k

[mrthanhnguyen]

2500k on Asrock z68 pro3-m. I overclocked it to 4.2ghz : base 100 * 42. In the bios, it states that cpu voltage is 1.32, and I choose offset mode. I also choose whatever below that to +0.03v. In turbo boost power, I set them: short and long to the value of 250. I disable spread spectrum,cie, c3,c6, and thermal. When I log in window and open cpuz, its say cpu voltage is 1.36v at 4200mhz, then it came back to 1.008v when core speed is 1600mhz. I run prime 95 and core speed is 4200.5, 4200.6, 4199.8. cpu voltage when running prime95 is 1.304-1.296. no crash, no bluescreen. I have a question about voltage. why it is so diffrent, prime95 is lower that when first boot into window and lower in the bios. is the core speed when running prime 95 change below and above 4200 is not normal. is it not stable? Must it be 4200 all the time?

 

[MGF Derp]

It usually isnt 4200 all the time. It is normal for the bclk to adjust by things like .01 in the CPU-Z window. If it passes a Prime95 test then it is stable and not to be worried about.

 

[mrthanhnguyen]

so what is the real vcore? With prime 95, I see only around 1.304v in cpuz, 1.371 in core temp, but when window boot up or normal turn on some app, i see vcore up to 1.36v in cpuz. Core temp also read 1.36v, is 1.36v is my vcore? is it high with 4.3ghz?

 

[MxPhenom 216]

so what is the real vcore? With prime 95, I see only around 1.304v in cpuz, 1.371 in core temp, but when window boot up or normal turn on some app, i see vcore up to 1.36v in cpuz. Core temp also read 1.36v, is 1.36v is my vcore? is it high with 4.3ghz?

yes 1.36 is a bit high for 4.3GHZ. However i think CPU-Z is more accurate.

 

[linoliveira]

I see you got into trouble here :b
1.36v is too much for 4.2GHz, try setting the offset voltage to something like -0.06v or -0.055v (wich will give you around 1.2v/1.22v and start working around it and see if it's stable, if not, go for -0.050v and so on.
I also recommend you to enable the power states, as you can manage to overclock the CPU without disabling them at least till 4.4GHz.

Good luck

 

[mrthanhnguyen]

so what is the vcore for 4.3ghz? not exactly but the close number. I tried to set at -0.015, and when window boot in, cpuz read vcore at 3.12v, but with prime 95, vcore at 1.264v. stable, no bluescreen or error? When I set at -0.05, bluescreen appear before log in to window. With -0.02, prime95 fail.

just tested with -0.015 with a longer time, prime 95 start to fail. set to -0.005, no fail, stable, vcore with prime95 is 1.272v-1.28v. window boot in with vcore 1.328v, vcore in bios is 1.296v.

 

[MxPhenom 216]

so what is the vcore for 4.3ghz? not exactly but the close number. I tried to set at -0.015, and when window boot in, cpuz read vcore at 3.12v, but with prime 95, vcore at 1.264v. stable, no bluescreen or error? When I set at -0.05, bluescreen appear before log in to window. With -0.02, prime95 fail.
http://i388.photobucket.com/albums/oo328/thanhnguyen89_2008/IMAG0111.jpg
http://i388.photobucket.com/albums/oo328/thanhnguyen89_2008/IMAG0112.jpg
http://i388.photobucket.com/albums/oo328/thanhnguyen89_2008/IMAG0113.jpg
http://i388.photobucket.com/albums/oo328/thanhnguyen89_2008/IMAG0114.jpg
http://i388.photobucket.com/albums/oo328/thanhnguyen89_2008/IMAG0115.jpg

just tested with -0.015 with a longer time, prime 95 start to fail. set to -0.005, no fail, stable, vcore with prime95 is 1.272v-1.28v. window boot in with vcore 1.328v, vcore in bios is 1.296v.

oh okay the VID thats shown in the coretemp is different then what voltage shown in CPU-z. just dont worry about the VID in coretemp pay attention to the CPU-Z voltage

For me im at 1.32v at 4.5GHZ and i still think thats still to high for 4.5GHZ i jsut havent fine tuned i just set it to that and called it a day.

 

[mrthanhnguyen]

So why the vcore is different when window boot and prime 95. I thought prime95 vcore should be higher,but white not. How about vcore in bios. Is it the true vcore?

 

[linoliveira]

So why the vcore is different when window boot and prime 95. I thought prime95 vcore should be higher,but white not. How about vcore in bios. Is it the true vcore?

That effect is called Load Line Calibration. When you are at idle state or when light load is applied to your CPU the Vcore will get to the BIOS Vcore (for around 1.27v ~ 1.28v in CPU-Z). But when high load is applied to the CPU the Vcore drops down a bit, lets say 1.26v.
If you want to play with it, just set the setting in the BIOS for level 4, and it will drop less when high load is applied to the CPU, but that's not necessary for 4.3GHz i guess.
Try disabling the Virtualization in the CPU settings and see if it helps in getting it stable.

Just one question, are you using/OC'ing the IGPU? if not, maybe set it to auto.
Also, what is your RAM speccs?

Here are my settings if you want to take a look:

 

[mrthanhnguyen]

Ii don't oc igpu ,but I install lucid virtu. I have not touch anything in the igpu. My ram is ripjaw gskill 1600 MHz. Leave it at auto.

 

[technicks]

The only thing i have done is go to the ''Load optimized cpu setting'' Change it to 4.6Ghz. Set the voltage for the cpu to 1.27v and Bobs your uncle.
Really no need to go and fiddle with all the settings. Just load default setting and try as i described. I won't hurt to try!

For the 4.2 you want i advise to set the CPU voltage to 1.25v. Also set the CPU voltage to ''Fixed'' and disable Intel Speedstep and the powersaving option in the CPU setting tab.

 

[mrthanhnguyen]

in asrock bios, there's no voltage option for u to choose. jsut -0.xxxx or +0.xxx. i tried to choose -0.05, or -0.045, window can't even boot coz bluescreen appear. vcore is 1.272 is the most stable i've seen in my system with prime95.

 

[linoliveira]

Try disabling the Intel Virtualization (Lucid Virtu doesn't use this, even if you use Virtu it will be ok) in the BIOS if you don't use it, and see if it affects stability. Also you'r RAM spec is 1.5v @ 1600 so i recommend setting it manually to 1.5v because the mobo is doing 1.54v.

After getting it stable, i recommend trying to turn the C states on, because they help when the PC is in IDLE state or on light load like browsing the web.

 

[technicks]

Like i said. If you set CPU core voltage to fixed it will let you set the voltage you want. I have a Asrock mobo so you better do some reading before you try to oc. There are many threads on the forum regarding this!
But do as you like. Overclocking a 2500K on your mobo is a piece of cake. You only make it hard on yourself.

 

[mrthanhnguyen]

How about igpu voltage? Just leave it auto

 

[linoliveira]

Like i said. If you set CPU core voltage to fixed it will let you set the voltage you want. I have a Asrock mobo so you better do some reading before you try to oc. There are many threads on the forum regarding this!
But do as you like. Overclocking a 2500K on your mobo is a piece of cake. You only make it hard on yourself.

Fixed voltage sucks srly... i won't let my CPU burn with constant voltage 24/7 thats for sure, if you want it, you are free to do it. I have overclocked with offset mode and never got an issue with it.

How about igpu voltage? Just leave it auto

yes, leave it auto

 

[technicks]

Well i oc'ed mine out of the box to 4.8Ghz without any hassle. So yes indeed this works for me. No offence but as far as i have seen your input hasn't made any drastic improvements, so let him try. These are my settings maybe they are usefull to you mrthanhnguyen.

 

[INSTG8R]

technicks that is a fine overclock no doubt but having it "pinned" 24/7 I wouldn't be game with. I mean I run 4.6 as well but still let it drop back to 1600Mhz, on water or not.
Good starting place for him but I would draw the line at turning off Speedstep and like. I personally run an offset and leave all the regular stuff on.

 

[technicks]

Why wouldn't you let it run @ 4.6? I mean it's not that my pc is on all day. Just when i am at home.
So for me i don't see any reason for not doing it. The only thing i can think about is the electric bill. But to be honest, i don't really care if i have to pay a few euro's more.

 

[radrok]

Doesn't make any sense to keep speedstep off unless you want to achieve borderline clocks to bench and this is not his case as it seems.

 

[INSTG8R]

Not only that running and OC is going to over time will degrade the CPU. I would rather have mine sitting at a nice 1.0V while it's doing nothing then having it run 1.25+ all the time for no reason.

 

[technicks]

This is going in the wrong direction. Do whatever you like.
I know what works for me and claims like ''It doesn't make sense'' and ''degrading the cpu'' makes me lol. These are still mild overclocks and the voltage raise is so minimal, your cpu would not be harmed by this running 24/7, if it's cooled properly that is. The options are power saving options and nothing else. You enable or disable them, thats it!

Btw, did you try it mrthanhnguyen?

 

[mrthanhnguyen]

ok. I just tried turbo 4.4 and saw the fix voltage is 1.25v, but when load prime95, the vcore up to 1.4v, so I just disable turbo mode, leave mine at 4.3ghz at 1.28v and it is the most stable. any voltage below 1.272 makes prime95 fail.

 

[technicks]

What is your cpu temp on load? And where does it say that the voltage goes up to 1.4v?
And btw the most stable. Isn't stable.

 

[CrAsHnBuRnXp]

What are your RAM timings? Might need to loosen them.

With my board (different board), my CPU voltage is 1.265 at 4.3GHz (havent tried for 4.5 yet), Internal PLL voltage disabled, ram speed at 2133 from 1600 and ram timings of 9-10-9-27 CR1. Im 100% stable, and ram volts at 1.65. Thats literally all ive changed.