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Intel Core i5 & i7 Sandy Bridge Overclocking and Feedback

can you drop initial votlage to 1.175v or lower?

how about playing with VRM frequency?

Those options are there for a reason! ;)

After more long term stress testing my previous post resulted in a BSOD.

I continued to experiment with 0% LLC, 160% current while increasing VRM frequency up to 700KHz and lowering initial vcore set in BIOS to between ~ 1.150v and 1.175v but I still seemed to have stability problems... BSOD while stressing and testing 45x, 46x and 47x.

This particular chip's VID with 0% LLC seems to show 1.160v in BIOS @ vcore offset -.005 and 1.168v/1.176v in BIOS @ vcore offset +.005.

I noticed that my board's power VRM heatsinks felt a little too warm/hot for daily 24/7 crunching use so I decided to lower current and VRM frequency settings some while bumping LLC up to 25% which shows ~ 1.195v in BIOS.

I was also able to drop VCCIO and VCCSA back to default/stock and lowered DRAM to 1.625v
4 dimms 2133 speed.

Vcore is reading ~1.303v load with a DMM.

2600K47xDigiVRM.png


2600K47x1195vBIOS140current25LLC.png
 
Looking good, gonna have to get myself some of those rams, for sure.

One thing to note is that ram speed seems to have a negative impact on cpu speed here, might be due to running 4 DIMMs though.
 
Wow that is high voltage!! At least temps are good though with it being under water :toast:.

Let me tell you this much. My cpu refuses to play at one notch below that voltage. The two voltages that allowed me to overclock this far are the Vcore and System agent voltage.

Intel claim these chips are good up to 1.5v So I don't mind running the voltage that high.

In fact I played some games last night and like I said the highest temp my cpu reached was 49c. Thats not bad at all. IBT really stresses the cpu and I don't think anything thing I do day to day will ever tax the cpu like IBT so I'm not worried.

How long will this last? Beats me and I really don't care. I'm gonna push this chip at this speed or greater 24/7 and if I kill it...so be it. I'll buy a 2600K and start over. But I have a feeling that this 2500k will run a long, long time.
 
Let me tell you this much. My cpu refuses to play at one notch below that voltage. The two voltages that allowed me to overclock this far are the Vcore and System agent voltage.

Intel claim these chips are good up to 1.5v So I don't mind running the voltage that high.

In fact I played some games last night and like I said the highest temp my cpu reached was 49c. Thats not bad at all. IBT really stresses the cpu and I don't think anything thing I do day to day will ever tax the cpu like IBT so I'm not worried.

How long will this last? Beats me and I really don't care. I'm gonna push this chip at this speed or greater 24/7 and if I kill it...so be it. I'll buy a 2600K and start over. But I have a feeling that this 2500k will run a long, long time.

Sweet. I have a feeling with those temps you are probably right. Either way, I'm gonna run mine safe until I know I can afford a 2600K and then I may go a little crazy with it just to have fun :D Even at stock though these chips are great and more than enough currently.
 
I agree LoM.

My bios allows me to save bios profiles and I have a stock profile setup, a 4.7GHz stable profile and my current stable 5GHz profile. I'm going to bench with all three profiles to see what kind of gain I get with overclocking.
 
My chip is weird :P ...... rock stable at 4.5ghz 1.325vcore for days now, but won't boot into 4.8ghz without PLL overvolting and an increase to 1.4+vcore ....

I had C1 enabled
Real time OS change enabled
CPU PLL 1.700
QPI/VTT 1.080
RAM 1.5

Is there anything I am doing wrong? Should I be increasing VTT at this point?
 
My chip is weird :P ...... rock stable at 4.5ghz 1.325vcore for days now, but won't boot into 4.8ghz without PLL overvolting and an increase to 1.4+vcore ....

I had C1 enabled
Real time OS change enabled
CPU PLL 1.700
QPI/VTT 1.080
RAM 1.5

Is there anything I am doing wrong? Should I be increasing VTT at this point?

CPU PLL should be 1.8000 by default no?

I think your chip is not strange at all. I can run low volts for a 4.5GHz OC too. In fact every where I look I see people using sub 1.4V for these chips when clocked below 4.8GHz but all the 4.8GHz and above clocks I see people mostly running 1.4v to over 1.5v
 
CPU PLL should be 1.8000 by default no?

I think your chip is not strange at all. I can run low volts for a 4.5GHz OC too. In fact every where I look I see people using sub 1.4V for these chips when clocked below 4.8GHz but all the 4.8GHz and above clocks I see people mostly running 1.4v to over 1.5v

Ah yeah but I lower CPU PLL since I've seen a bunch of people do the same :). Thanks man, I guess I am just expecting too much from my chip :laugh:
 
What would be the reason for running PLL under its default voltage? I'm just wondering what gain it would provide?
 
What would be the reason for running PLL under its default voltage? I'm just wondering what gain it would provide?

Well for some boards it helped people stabilize their overclocks at lower amounts of vcore, worth giving it a try to see if it affects your clocks. I don't think it affects mine but I'll play with it some more today.
 
I did play with it but it didn't help me one way or the other. So I just left it alone. Thanks Random.
 
Interesting, Gigabyte B3 boards have now got an F3 BIOS release.

They seem to have addressed LLC by completely changing the option to something called "Multi-Step Load Line" It has 10 levels compared to the standard/1/2 levels on the previous versions. So far after some testing I am able to reduce the voltage drop by a lot during load.
 
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Dear friends, some questions regarding overclocking my i5-2500K. It is the first time I try this and don't want to get on the extreme side of things just mild stuff with (for now) the stock cooler. After doing some research I did the following. On the ASRock P67 Extreme4 in the UEFI BIOS I changed manually the multiplier to 40 and set the VCore to fixed 1.225V. Everything seems to be fine, ran Cinebench max temp 72.

Now is it perfectly safe to keep the Vcore fixed, are any downsides to this and damage in time? This 4 GHz is in fact the turbo freq as it still idles at 1596 MHz (31 temp)?
Why is CPU-Z showing me the Bus speed at 99,8 instead of 100?

Many thanks in advance
 
Now is it perfectly safe to keep the Vcore fixed, are any downsides to this and damage in time?

Nope, you are well within the safe zone. That said, your clocks are so low that I'd even take it off of fixed mode, and let it go up as it normally would with turbo.

This 4 GHz is in fact the turbo freq as it still idles at 1596 MHz (31 temp)?

Maybe, but maybe not, might just be EIST kicking in. It's all good, anyway.

Why is CPU-Z showing me the Bus speed at 99,8 instead of 100?

Because dropping the bus to just below 100mhz alows for an extra multi at the high end.

Many thanks in advance

No problem. ;) Just FYI, you could probably get away with even lower volts.
 
In fact I tried to lower volts (fixed that is) but I got Windows hard locked so got back to this sweet spot. I tried before with ASRocks in UEFI BIOS auto OC setting at 4GHz where I assume the Vcore runs freely but I got pretty high temps in Cinebench and even tried Prime but quickly stopped it since it went way over 80 and rising. So I think that by fixing the max Vcore, the temps are more acceptable, remember I'm still with stock cooling on the i5. Anyway we only game and office work so don't really need to go higher. I can't stop being amazed by this CPU. Just with a few clicks one can get 15-20% OC and breaking the 4GHz barrier with a stock cooler. My first Pentium 2 ran on 350 Mhz... Nice to be part of TPU community
 
In fact I tried to lower volts (fixed that is) but I got Windows hard locked so got back to this sweet spot. I tried before with ASRocks in UEFI BIOS auto OC setting at 4GHz where I assume the Vcore runs freely but I got pretty high temps in Cinebench and even tried Prime but quickly stopped it since it went way over 80 and rising. So I think that by fixing the max Vcore, the temps are more acceptable, remember I'm still with stock cooling on the i5. Anyway we only game and office work so don't really need to go higher. I can't stop being amazed by this CPU. Just with a few clicks one can get 15-20% OC and breaking the 4GHz barrier with a stock cooler. My first Pentium 2 ran on 350 Mhz... Nice to be part of TPU community

Ah, stock cooler. And yes, 4ghz is MORE than adequate. I was going to skip Sandybridge, but had to buy for reviews, and since then, I've completely fallen for the P67 platform, as it not only exceeded my expectations, but did so with so much ease that it's become hard for me to find a negative side of the platform, other than it making my recently purchased i7 870 obsolete, performance-wise!
 
Anyone else who received the "Multi-Step Load Line" Function? I just did a bit more research and overall it's been giving people more control over VDROOP. Although it seems so far levels 1-10 vary on different Gigabyte boards, so some may start overshooting at earlier levels than others it seems.

Here are the results

My previous settings were

Level 1 LLC
BIOS Vcore at 1.325
Load - 1.284
IDLE - 1.320

New Settings

BIOS Vcore at 1.305
Multi-Step LL at Level 6

Load Voltages 1.284/1.296
loadvoltage.jpg


Idle Voltages 1.308
idlem.jpg
 
I've done my preliminary stability run of my new rig. Got up to 4.7 ghz so far.

Vcore - 1.355 set in bios. 1.344 - shows in bios/windows when idle. 1.320 under Prime. I had to turn LLC 1 on, because otherwise the v-drop was quite a substantial one, and I failed to run evet OCCT at 50% load.
Specs:
i7 2600k
Gigabyte P67A-UD7-B3 bios F2
2x4 gb ddr3 g-skill 1600 8-8-8-24 ram
Noctua DH14
All energy saving functions are desabled.
Temps under load : max. I've seen was 56, then they droped and stayed between 51-54. Which is quite good I think.
Here's a quick question: is it safe to keep this OC under currect vcore setting? or should I reaaly strive to lower it down?
Thanks
 
It seems without the K 3.9GHz is the fastest one can go. Is that true? Even setting the multi in the BIOS to x40 it reverts back to x39. But in the BIOS it says the limit is up to x42...
 
It seems without the K 3.9GHz is the fastest one can go. Is that true? Even setting the multi in the BIOS to x40 it reverts back to x39. But in the BIOS it says the limit is up to x42...

42 might be single-core only.;)
 
Does Intel Burn Test have to lock up? Mine locked up and hang after the 15th test LOL

Temps maxed at 70C, but hovered around 62-66C most of the time.
 
I just logged into my remote desktop from work...or I tried to but couldn't because my pc shut down nearly three hours ago. I know when I go home I will see a BSOD on my screen.

The other day I switched my memory timing from 2T (default) to 1T and the memory doesn't like running 1t. Oh well. Once I switch back I should be stable again. At least I was before messing with memory timings.
 
Anyone else who received the "Multi-Step Load Line" Function? I just did a bit more research and overall it's been giving people more control over VDROOP. Although it seems so far levels 1-10 vary on different Gigabyte boards, so some may start overshooting at earlier levels than others it seems.


So, you like the granularity on the current you are adding? Good deal. ;)
 
Well here's my 2 cents:cool: :


Since I use LL2 to stabilizve Vdrop, vcore is 1.356 under actual load. Also my temps on TMPINs had a crazy spike, I guess the sensors flipped on me at some point, hense the impossible 110-120c temps.:D

Anyway, I think 25 runs in LinX is sufficient enough to call it stable for 24/7 use in light video rendering and some heavy gaming.:)


P.S. IDK if it is the bios F2 I'm using, or the fact that I didn't touch QPI/VTT settings or something else - but I can't boot starting at x49. I get the UD7 fancy picture and then my PC restarts, and when I get to bios I get "OC failed" screen. I tried with voltages up to 1.37 + LCC2 with no luck.:confused::shadedshu
Also I have problems with my reset button. IDK if I connected the wires wrong, or something, but whenever I hit reset my bios setting get corrupted.:mad:
 
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