Problems Overclocking 2500K

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genjaguar

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So I'm not sure if I've run into a wall or I'm doing something wrong...but I can't get my 2500K past the 44x multiplier. I boot to windows fine at 44x with just 1.3vcore. But if I try 45x+ it will not even get to the loading windows screen. Just leaves me at a screen with a blinking cursor after my MB BIOS screen. I tried voltages all the way up to 1.48 and still would not boot up.

Did I just hit a wall with my chip or is there something I'm doing wrong? Is there some other settings I should be changing?
 
Solution
I normally don't do this, I expect people to learn what they're doing first then do it, but seeing as how Sandy Bridge is totally new overclocking territory and you have the same motherboard I do, I'll give you the necessary BIOS settings to allow you to discover your multiplier/vcore combination to run the various speeds, I'm not going to give you those exact settings some of this overclocking adventure you're going to do on your own.

Under Advanced
v
CPU Configuration
v
Active Processor Cores = All
Hardware Prefetcher = Enabled
Adjacent Cache Line Prefetcher = Enabled
Enhanced Halt State (C1E) = Disabled
CPU C3 State Support = Disabled
Package C State Support = Disabled
CPU Thermal Throttling = Enabled...
You hit your Sandy Bridge CPU's "multiplier wall" -- the multiplier which it cannot pass no matter how much voltage you feed it. Every Sandy Bridge has one, and it's different for each particular CPU.

Some are unlucky and get only 4.2GHz, average is 4.4-4.5GHz, and 4.8-5.0GHz is the common top-end. A very rare few get past that.

My 2500K gets 4.8GHz in an ASRock P67 Pro3 B3 board.

Edit: Question ... do you have Internal PLL Overvoltage (or similar) set to Enabled? If not, do it and try again. You may be able to get higher.
 

genjaguar

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What kind of risk with data corruption is there? And I thought most chips would be able to do more than just 44x...I know that's already a fairly high OC over stock but I can't help but be disappointed when I know my cooling could handle more.

Nothing else can increase the multiplier? I was looking forward to getting close to 5ghz but I guess that's pretty much unreachable.
 
The clock generator for the PCI, PCIe, SATA, USB, and every other board function is within the CPU itself, and the clocks for those are not locked into a safe speed like when the clock generator is on the board. SATA especially doesn't like to go beyond its default speed.

Nope, that overvoltage setting is the critical one. If that didn't do it, you're screwed. The average Sandy Bridge overclock is 4.5GHz, so you're right in the ballpark.
 

Bigmac80

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Honestly anything pass 4.2ghz on the new sandy bridge cpu is pretty much overkill...Not unless you wanna show off some benchmarks...I have my i5 2500k at 4.2ghz at 1.2 volts running very cool at 50c running prime 95....To be honest with you i really don't see the difference in performance between 3.3ghz and 4.2ghz while gaming....
 
@genjaguar

More information would help in helping you for example all your present BIOS settings and CPUs functions what you have enabled and disabled, including the overclock CPU functions?

Are you attempting to increase the base clock past 100mhz, if so, don't!

Is your memory timings and voltage locked in, if not do so!

Answer these and we'll see if there's a noticable problem?

 

genjaguar

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Was my fault for not stating all of that.

I am using the ASRock Extreme 4 B3 revision. I just put my new build together.
I run Ripjaw X 1600 @ stock settings.

I did not even mess with changing the Base clock past 100 mhz before( I tried after the post a few up but no luck booting at 101mhz).

I did not mess with too many settings in my BIOS.
I have Speedstep disabled(for some reason my multiplier was stuck at 16x no matter what I did so I disabled mostly anything with power saving or throttling), C3 disabled and package c state limit disabled, and CPU thermal throttling disabled.(I had C1E disabled but after reading some articles and how it helps with OC I re-enabled it although now I do go down to a 16x multiplier sometimes)

I haven't changed any other settings from defaults.
 




No offense but you have not hit a multiplier wall, you're not getting the overclock you're after simply from a lack of knowledge, read this overclock guide.

http://www.tomshardware.com/forum/265056-29-2600k-2500k-overclocking-guide

Do Not Disable Thermal Throttling

Do Not Increase your Base Clock, Leave it at 100mhz

Do manually lock in your memory voltage and timings

You have not mentioned temperatures, what CPU cooling are you attempting to do this with?
 

genjaguar

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I am using a Hyper 212. My temps at idle are in the low 30s and with my OC during Prime95 it was around the mid 50s.

I will enable thermal throttling again. I haven't touched the base clock since trying it once...so I am leaving it at 100mhz. I will also make sure to lock in my memory timings and voltage.
 
I normally don't do this, I expect people to learn what they're doing first then do it, but seeing as how Sandy Bridge is totally new overclocking territory and you have the same motherboard I do, I'll give you the necessary BIOS settings to allow you to discover your multiplier/vcore combination to run the various speeds, I'm not going to give you those exact settings some of this overclocking adventure you're going to do on your own.

Under Advanced
v
CPU Configuration
v
Active Processor Cores = All
Hardware Prefetcher = Enabled
Adjacent Cache Line Prefetcher = Enabled
Enhanced Halt State (C1E) = Disabled
CPU C3 State Support = Disabled
Package C State Support = Disabled
CPU Thermal Throttling = Enabled
Intel Virtualization = Disabled---->----If you run a virtual operating system like WinXP inside Win7 then Enable this.
No-Execute Memory Protection = Disabled

***************************************************************************************************

OC Tweaker
v
CPU control
v
CPU Ratio = Manual
Max Ratio = ?? Multiplier
Internal PLL Voltage Overide = Enabled
Intel Speedstep Technology = Disabled
Turbo Boost Power Limit = Auto < If this even shows up in your BIOS leave on AUTO T/B will already be disabled
Additional Turbo Voltage = Auto < If this even shows up in your BIOS leave on AUTO T/B will already be disabled
Core Current Limit = 150
Host Clock Override (BCLK) = 100.0mhz

***************************************************************************************************

Voltage Control
v
Power Saving Mode = Disabled
CPU Core Voltage = Fixed Mode
Fixed Voltage = ?.??? ___I will tell you you should be able to run a 45x multiplier somewhere around 1.300v to 1.325v
CPU Load Line Calibration = Level 1
DRAM Voltage = Whatever your memory modules require
Leave everything below on Auto

Good luck To You! Ryan

Additional Note: DO NOT EXCEED 1.50V ON AIR COOLING
 
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genjaguar

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Thank you for all the suggestions ryan. I usually do overclock my builds by myself with some research. I actually enjoy discovering what I can do and push my system to do.

I have set everything like you said and also manually set my timings for my ram like was suggested...however again it never started windows...just gets to the screen right after bios with a blinking cursor.

I tried vcore from 1.3 all the way to 1.47 and the 45x multiplier would not boot( I also tried 46x just in case but it would not boot either). It seems like I could have hit my multiplier wall...otherwise I am at a loss.

While I do overclock my system...I never messed with a lot of the settings just in case I could cause some damage. I usually mess with voltages and multipliers and front bus frequencies...so that is why I was not sure what else to change on this build( this is also the first BIOS that has had a ton of options to change for me).

I also read through the post you linked earlier...and that had some conflicting settings from what you suggested so I tried those...still no luck booting up. (speed spectrum disabled, intel virtualization enabled).

Of course changing it back to 44x boots up perfectly at 1.3vcore(I was running 1.3vcore before but have lowered it since and it actually boots perfectly at 1.25vcore in BIOS, haven't prime tested it completely yet) .
 
Unfortunately, the multiplier wall is insurmountable.

You've confirmed that your maximum speed is 4.4GHz. Now that you have messed with all the nice power-saving settings the Sandy Bridge CPUs were designed to have enabled, I would suggest resetting your BIOS back to default and simply using the "Turbo 4.4GHz" preset for your everyday overclock. Change your RAM to use the correct XMP profile (or manually input the timings), but leave everything else at default.

That way the system will be in 1.6GHz low-power mode most of the time, and jump to 4.4GHz high-power mode when needed (like when you play a game). The CPU voltage will also go up and down based on processor load.
 
@genjaguar

Just out of curiosity have you ran any memory diagnostic tests to make sure your memory isn't producing any errors?

Did you completely clear the BIOS and start from scratch?

You could possibly have a CPU that will run the higher multipliers on lower voltage, that's why you basically start your testing at lower voltages and work up, to run the least amount of voltage required to stabilize at a certain multiplier.

*************************************************************************************************

Anyway you have my setting suggestions and Leaps-from-Shadows back to default suggestion re-enabling the Intel power saving features.

If 44x is the highest multiplier you can run, performance wise I suggest testing it both ways and seeing which way gets you the most performance, 4400mhz running all 4 cores is very performance impressive with that CPU, but you need to decide that for yourself.



 


Unfortunately that just may be genjaguars luck of the draw.

However 4400mhz is still impressive with all 4 cores running, that's still an 1100mhz OC, and one heck of a performance increase.
Better than any overclock I got from AMD on air cooling.
 

The "Turbo 4.xGHz" presets in the ASRock UEFI/BIOS turn the Turbo multipliers of all the cores to the same value. I run mine on the Turbo 4.8GHz setting, and no matter how many cores are loaded it runs at 4.8GHz. Playing a single-core game? 4.8GHz. Stability testing all cores with Prime95? 4.8GHz. I use that setting simply because it allows the processor to go into low-power idle mode most of the time and then jumps to full 4.8GHz speed when I need it. I would run it using the settings you suggested, but I don't need a 4.8GHz Sandy Bridge to check my E-mail or use OpenOffice or surf the web (which is what I do most of the time). A 1.6GHz Sandy Bridge is good enough for that.
 

genjaguar

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So tried a couple more things and I got some very weird results.
I cleared my CMOS and started from scratch...used the settings that ryan posted and tried booting with a 45x multiplier. Tried voltages from 1.27(ran 44x fine) all the way to 1.41 in .2 intervals with no luck. I then tried 46x at 1.41 with again no luck.

However, then I tried 47x at 1.41 and it booted. I got into windows ran some quick tests and it actually worked. So again I rebooted and tried 48x and that worked as well. Currently I am using 49x at 1.415vcore and it seems stable(ran some quick tests like Super Pi for basic stability but will still need to run prime to test further).

I tried lower vcore than 1.415 but that is what 49x took. For 47x it was booting and seemed stable at around 1.375 and 48x took about 1.4. I know I need much more testing to determine how stable those are, but just as a basic idea that is what my results have been.

Knowing 49x boots and seems stable I tried 50x,51x, and 52x just in case but none of those booted with vcore all the way up to 1.46. Even so 49x is very impressive...but not sure why the weirdness occured.

There is something I'm concerned about and that is my temps. At 1.415 in BIOS I get idle temps at around 37-40 for the hottest cores. At load my temps go to around 65-67 for the hottest cores. Is that still ok or is that too high. During the quick prime test I ran to see my load temps I saw cpuz show a vcore of 1.44.

Another thing is...when running prime I saw my multiplier drop...it went to 43x or 42x. It even dropped to 40x. As soon as I turn off prime it goes back up to 49x. Is that normal? (I'm guessing thats the thermal throttling in action)

As for my memory...I ran a few passes of memtest with no errors but will need to do much longer tests to make sure the ram is fine
 
Okay you have some sort of special quirky board/CPU combo.

And no, it's not thermal throttling. That lowering of the multiplier when in Prime95 is the CPU running into the power limit.

Change these...
Turbo Boost Power Limit: Manual
Short Duration Power Limit: 300
Long Duration Power Limit: 250
The setting below that: 56 (or whatever the maximum is)
 



There we differ, I like mine pedal to the metal, all 4 cores at whatever multiplier I decide to run them at, I just like it like that, desktop nice and snappy, apps opening almost instantaneous, if I wanted it to run 1.6ghz, I'd just use my cell phone.
 


If you could even boot at those multipliers, I'd say you don't have a 44X multiplier wall after all, you just need some vcore fine tuning of what you can boot to.
 

genjaguar

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Well I tried tons of vcores...and 45x will not boot. Vcores ranging from 1.27(boots 44x) and 1.41(boots 49x) and through none of those did 45x boot. So I don't think it's a vcore issue.
 
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