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[O/C]3 Step Guide to Overclock Your Core i3, i5, or i7

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1st question - are you using the iGPU? If so, did you read this section?
MIAHALLEN said:
Isolate the bclock from the iGPU (Clarkdale only)
2nd question - what was the maximum stable bclock freq you found in step #1?
 
1st question - are you using the iGPU? If so, did you read this section?

2nd question - what was the maximum stable bclock freq you found in step #1?

1st question - are you using the iGPU? If so, did you read this section?

2nd question - what was the maximum stable bclock freq you found in step #1?

Sorry i forgot to mention i have the hd 5750.

I'm not at home so i can't test the maximum stable bclock right now, but the highest i could get so far (with memory timings set manually and mem volt set to auto, mem at 2:6) was 185 block (what im aiming for) x 19 multi @ 1.08 vcore and 1.21 vtt (would you recommend leaving vtt at stock 1.10?) which posted at 3.51ghz. Everything else was set to auto. I tried running 185 x 21 loaded windows then got the BSOD. I ran prime95 before I left, and it was stable for 5 minutes @ 185 x 19. It's still running so ill check the stability when i get home.

I also ran prime95 overnight with the settings in my previous post and got an error after one hour so that one wasnt stable -.-.

I forgot to mention that when i set the mem timings in the BIOS 9-9-9-24, cpu-z reads it was 7-9-9-24. Is this normal?

Im trying to hit 3.9-4 ghz using the lowest vcore. If possible not exceeding 1.25 vcore.
Thanks!
 
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Sorry i forgot to mention i have the hd 5750.

I'm not at home so i can't test the maximum stable bclock right now, but the highest i could get so far (with memory timings set manually and mem volt set to auto, mem at 2:6) was 185 block (what im aiming for) x 19 multi @ 1.08 vcore and 1.21 vtt (would you recommend leaving vtt at stock 1.10?) which posted at 3.51ghz. Everything else was set to auto. I tried running 185 x 21 loaded windows then got the BSOD. I ran prime95 before I left, and it was stable for 5 minutes @ 185 x 19. It's still running so ill check the stability when i get home.

I also ran prime95 overnight with the settings in my previous post and got an error after one hour so that one wasnt stable -.-.

I forgot to mention that when i set the mem timings in the BIOS 9-9-9-24, cpu-z reads it was 7-9-9-24. Is this normal?

Im trying to hit 3.9-4 ghz using the lowest vcore. If possible not exceeding 1.25 vcore.
Thanks!
OK, my first thought was this was iGPU related, and they almost always start giving problems around the same bclock range, but getting that out of the way, we're on to bclock and CPU OCing....steps #1 & #2 in the guide.

So when you tested for high bclock, you were using 185MHz with 1.21V VTT correct? You also had the CPU multi at x19??? Try for max bclock again with CPU multi set to x12 or so. If your goal is for 185MHz bclock, then got 190MHz stable for at least 1 hour. You may need more VTT...1.21V is not a lot, running 1.35V is perfectly safe for an air cooled rig ;)

Then go back to 160MHz and bump up the multi to you desired setting, and the CPU voltage to 1.25V, then 5MHz at a time test as described in the guide and see if you can get it back up to 185MHz bclock. You may not get there though with so little voltage. Most CPUs need at least 1.3-1.35V to get to 4GHz, but you'll never know until you try. :)

If you need more help, please start a new thread so this one can remain on the topic of the guide :thup: Thanks, keep us posted :cool:
 
I'd like to formally thank you for the help :). Was able to get 3.85ghz stable at low volts following your steps. Great guide !!! Thanks again.
 
So when you tested for high bclock, you were using 185MHz with 1.21V VTT correct? You also had the CPU multi at x19??? Try for max bclock again with CPU multi set to x12 or so. If your goal is for 185MHz bclock, then got 190MHz stable for at least 1 hour. You may need more VTT...1.21V is not a lot, running 1.35V is perfectly safe for an air cooled rig ;)

Maybe this is a silly question, but is 1.35V really safe for an i5-750? I ran across this Anandtech thread stating the Lynnfield max is 1.21v VTT, while the older Bloomsfield is 1.35v VTT. I'm completely new to overclocking so I just want to make sure I'm as informed as possible and don't make any major mistakes. Thanks!

FYI, I plan to use your guide MIAHALLEN. It's the best one I've seen and I already have it printed out. ;)
 
The Vtt suggested by Intel is way off. Additionally, in order to run a larger ammount of RAM, you will need to up your Vtt. Call your RAM manufactuerer and they should clear this up for you. I run my i7 860 at 1.41V Vtt. If I am overclocking at 4GHz anything less than 1.25V will BSOD on me and anything less than 1.2 won't even boot.
 
Yup...Brutal is correct...1.35V is perfectly safe...I know many users who run more. I run my Bloomfield at 1.5V 24/7 :thup:
 
Nubian with i5 661 wants to start 1st overclock.

Cool article ! I'm going to apply this.... I've been reading articles for about 40 hours or more, but have to say there is a shortage of up to date beginner guides for noobs like me, so i'm gratefull for the info. Read it several times while surfing web for info.

Specifications:

i5 661 (stock)
4GB PC3-10666 1333MHz
Asus P7H55-M Pro
Radeon 5770 1GB GDDR5
Dual Layer DVD Burner
Hard Drive: 500GB
Cooler Master eXtremePower Plus 600w
Case: Cooler Master Centurion 590
Windows 7 Home Premium 64bit


My goals:

I'd like 3.7-3.9Ghz Nominal with room for Intels' Turbo Boost taking me to 4Mhz. According to my research my target should be about a 150 -155 MHz bclk and near stock volt's.

I bought this system and installed BFBC2 after playing BF2 for years, it does ok, but I have to turn down AA, AF HBOA = off to get 50 fps. If I want 60fps I have to drop res from 1900

1a) IYOP, what's my bottleneck ? CPU or GPU ? I plan to O.C both if I have to.

1) Does the iGPU chipset switch off entirely when you add a graphics card into the mix ? Do I still have to tweak the BIOS settings for the iGPU as instructed in GUIDE or can I forget about them for the OC?

2) OC'ing parameters aside, resetting the BIOS to default settings is scary to me, I've never done it before, never had a reason to. Wasn't it config'd by the builder in the shop for my specific system ? Is there a chance that other important settings besides the ones used for OC' be affectied negatively ?

3) Please confirm... Disable Turbo-Boost and Speed-Step ? Disable before starting to OC or leave enabled ?

Thanks to all who respond !
 
:welcome: to OCF :)
I'd like 3.7-3.9Ghz Nominal with room for Intels' Turbo Boost taking me to 4Mhz. According to my research my target should be about a 150 -155 MHz bclk and near stock volt's.

I bought this system and installed BFBC2 after playing BF2 for years, it does ok, but I have to turn down AA, AF HBOA = off to get 50 fps. If I want 60fps I have to drop res from 1900

1a) IYOP, what's my bottleneck ? CPU or GPU ? I plan to O.C both if I have to.
Lots of folks want to talk about bottlenecks, but it's a more difficuly question to answer than most people think. Why? Because it totally dependant on a ton of variables. But thank goodness you asked the question correctly, telling me all of the hardware and what you plan to run (BFBC2). In this case, I'd say your GPU will be a bit of a bottleneck in most instances, expecially at native resolution as you've already discovered. So if I was you, I'd try to get that thing OC'ed first....or upgrade it if you can afford it. ;)
1) Does the iGPU chipset switch off entirely when you add a graphics card into the mix ? Do I still have to tweak the BIOS settings for the iGPU as instructed in GUIDE or can I forget about them for the OC?
The iGPU switches off entirely since you're using a dedicated card. Don't worry about it :)
2) OC'ing parameters aside, resetting the BIOS to default settings is scary to me, I've never done it before, never had a reason to. Wasn't it config'd by the builder in the shop for my specific system ? Is there a chance that other important settings besides the ones used for OC' be affectied negatively ?
No, the builder likly didn't change anything in the BIOS, and from the factory, it should be at defaults anyway, so resetting them to defaults won't likely change anything
3) Please confirm... Disable Turbo-Boost and Speed-Step ? Disable before starting to OC or leave enabled ?
You've layed out your goals pretty clearly for me, and I think they are attainable. So in your case no, do not disable them. Just up your bclock step by step, and check for stability. I wouldn't change any voltages either, auto settings should work fine. Although keep an eye on the voltage displayed in CPU-Z while you are stress testing to be sure the board isn't setting rediculously high "auto" Vcore...if it is, you may have to take voltage settings into your own hands. My guide was more targeted at users looking to push a little harder, say if you wanted to shoot for 4.5GHz or so...then you would most likely HAVE to disable those features mentioned....
Thanks to all who respond !

If you have any more questions, please start a new thread so it will get more visibility from the whole community :thup:
 
nice guide mia it was informative and will help me with pushing my new i7 system and seeing its limits.
 
Sorry, I don't have time for a proper reply now, but I will address your post when I return from a quick trip in a couple days (walking out the door in a few minutes)....great suggestions here :thup:
 
I got one question for you miahallen, when you say it's dangerous to have the VTT and VDIMM more than 0.5V apart, does that mean you want to minimize this difference as much as possible?

I am working on an overclock that is stable with VTT at 1.17V. I am currently running my ram at 1.66V. I don't know what is better, running my VTT lower or perhaps making my VTT closer to my ram voltage. I assume you wrote that in to mean for the case where people are putting lots of voltage on their ram, but I'm wondering what's the best setting for my particular chip.
 
I got one question for you miahallen, when you say it's dangerous to have the VTT and VDIMM more than 0.5V apart, does that mean you want to minimize this difference as much as possible?

I am working on an overclock that is stable with VTT at 1.17V. I am currently running my ram at 1.66V. I don't know what is better, running my VTT lower or perhaps making my VTT closer to my ram voltage. I assume you wrote that in to mean for the case where people are putting lots of voltage on their ram, but I'm wondering what's the best setting for my particular chip.

If you're stable, then there is no need to raise your VTT as you're within the cuttoff. Low VTT will definitely help lower your core temps. I wouldn't try to go any lower though ;)
 
Yeah, I'm actually more stable at 1.17 VTT than at 1.35 VTT, I have no idea why, maybe I need to do more testing. I almost wanted to go lower, but haven't in fear that I might damage my CPU. What else is strange is that my ram is more stable at higher voltage than before, like I said I probably need to do more testing. Could also be because I got a new motherboard.

I got a replacement cpu from Intel, and I've been messing with it. It has a very strange batch number, L003B806, and has a very recent pack date 4/27/10. Requires a lot more voltage than my last chip to be stable for LinX, but runs cooler than my last one by more than a few degrees, even at higher voltage. I'll test out some more when I get my Venomous X in the mail.
 
Bruce, thanks again for your comments, please see my answers to your questions below :)

Questions:
• “to +0.2V” in the text, or should it be “by +0.2V”? – in Bclock voltages section
• Should “+0.5V of the CPU Vtt value” be “+0.5V above the CPU Vtt value” – in the Maximum safe memory voltage section
Thanks for those :)

• Is there such a thing as IOH on a LGA1156 motherboard with H55 chipset? What should you do with IOH when you have no PCIe cards (only using the Clarkdale iGPU)? – in the Bclock voltages section
No, all P55/H55/H57 based boards use a Platform Controller Hub (PCH), it should not need any adjustment for basic overclocking, leave on "auto"

• Is there such a thing as ICH on a ASUS LGA1156 motherboard?
no

• By following the 3-step guide, should I be ignoring ASUS DOCP and XMP profiles?
yes

• Should I be enabling the ASUS Xtreme Phase Full Power Mode (instead of the Auto default)?
depends, for maximum overclocking potential, you should enable it. If you are concerned about saving power, you should leave it disabled

• Should I be using Offset or Manual CPU voltage when I need to change it, or doesn’t it matter?
manual (this corolates to the "power saving features" mentioned in my guide

• Should I disable the ASUS CPU TM function during my OC testing?
shouldn't make any difference

• Is the Uncore Frequency the same as the ASUS iGPU frequency on a Clarkdale CPU?
NO! The uncore on all LGA1156 CPUs has a fixed ratio in relation to the bclock frequency....the iGPU frequency can be adjusted in most H55/H57 BIOSes ;) See the section "Isolate the bclock from the iGPU (Clarkdale only)" under step #1

• Is the QPI/CPU Vtt voltage the same as ASUS IMC voltage?
yes

• Is the memory multiplier ratio you are talking about the same as ASUS DRAM frequency?
yes

• At what point in this Guide do you re-enable EIST, C1E, C-State (which package limit?), and the CPU TM function?
My guide is not geared to finding the best OC with these features enabled. If you intend to enable these features, then enable them from the start. This is because your OC limits will differ (will be lower) with these features enabled.

Thoughts/Suggestions:
• Start putting footnote references when something only does/not pertain to Clarkdale/Lynnfield/H55 or other chipsets/combinations
Great idea, might have to do this on the next revision.

• Consider adding a table of terminology you use vs. some of the common motherboard manufacturers (included at the end for my ASUS P7H55D-M EVO using the 903 BIOS)
While this would be idea, please keep in mind that this would be pretty difficult for me without having my hands on more equipment. I'm just an enthusiast doing this voluntarily at home. Currently I only have 1 LGA1156 motherboard and X58 motherboards from only 2 vendors. ;)

• Consider adding that the Clarkdale iGPU clock (x) should be calculated to be the default base clock (b) times the default iGPU clock (c), divided by (over) the OC base clock (a). So x=bc/a Example: an i-3 Clarkdale with its iGPU clock at 733 and default bClock at 133, and it is to be overclocked to 210, the iGPU clock should be changed to 733x133/210  464 (as a math teacher, I simplified a forum post here to make it easier to calculate)
This is covered in the section "Isolate the bclock from the iGPU (Clarkdale only)"....just without the formula. I think it's a good idea to add the formula though, thanks!

• terminology –
o say “SpeedStep (EIST)” so the next person does not have to look it up
o say how IOH Core Voltage is related to certain “Northbridge” chips? Elaborate with another sentence? Is H55 Northbridge?
o Say how ICH Core Voltage is related to certain “Southbridge” chips? Elaborate with another sentence?
• Spelling, if you want it even more professional – “ferquency”, “that” should be “than”?, “manufactures” should be “manufacturer’s” – search and replace
Great suggestions, thank you! :)

Again, thank you Bruce....and :welcome: to OCForums :)
 
Added Questions for The Guide:
• Can you also add just a couple sentences in The Guide on the aims for different OC’ers? Is the aim to have a balance between the highest BClockxmultiplierhighest CPU-z Core Speed without having to sacrifice much memory underclocking in a i-3 Clarkdale using the iGPU? Used as a multitasking computer (A Gamer/Jedi I am not) – when I need that last boost when concurrently doing huge Word Tables in my Chinese dictionary (I’m struggling to learn Chinese), 100MB digital picture manipulations for the family history, or huge spreadsheet reiterative calculations? Or when Windows 8 requires even more processing power in a couple years? Or for bragging rights? Which is better, for example… 182.4MHzx22 (4.013Ghz) w/memory at 729.6MHz, or 195MHzx20(lower 3.900GHz) w/memory at a higher 780MHz? And Why?
This is not a black and white Q/A....it depends on the app. But usually CPU speed trumps memory speed. And with the minimal differences you're aking about, both would feel about the same, but my advice would be to maximize CPU speed, not mem speed.

• To try to overclock the iGPU – do I just try to up the speed beyond the default (after calculation from the base)? What do I do with the 1.15v it by default AUTO-picks? Is there a non-ASUS utility that properly displays the iGPU frequency/voltage – because CPU-z seems to have it locked at 733MHz and I’m not sure I trust TurboV because it is the only source and seems to differ from CPU-z and others.
There is an app called "GPU-Z that should show the frequency, for voltage monitoring, Asus Turbo-V is the only option. Safe voltages for the iGPU are not known at this time. Most overclockers are gamers and therefore have dedicated GPUs and will not use the iGPU. But I do have a small amount of experience overclocking the iGPU due to a competition at HWBot.org a couple months ago. Many users were running the iGPU in excess of 1.4V and I did not here of anyone killing a CPU/iGPU during the contest. Having said that, if you are concerned about the health of the chip, I would recommend not giving the iGPU more than 1.3V until we have more data on the subject. BTW most of the Clarkdale iGPUs have been shown to easily break 1000MHz ;)

• Leaving things in BIOS at the default AUTO setting – I see ASUS wants to AUTO over-rate my memory to CAS8 (when shown in CPU-z) instead of the less expensive CAS9 mine is. When attempting to override (Should I override?), even the Memory Timings terminologies do not seem consistent between CPU-z and ASUS BIOS. Where do I set tRC? And how do I know the proper 2nd and 3rd ASUS sets of numbers in BIOS for my Corsair XMP 1600 memory? (wish I could put more characters regarding my “system” out here on the forum) Or is that translation table the subject of another Guide somebody wrote?
Interesting, usually "auto" does just the opposite :p The numbers in CPU-Z SHOULD all be represented in the BIOS....and they are the only ones I would adjust (there will be many others as well). Check again, if they are not all there....maybe you could post some shots of the BIOS screen and we can assist more.

• Should the IMC/CPU Vtt voltage generally be kept over or under the VCore voltage by a certain amount? Maximum difference?
There is no specific rule for this, as mentioned in my guide the 32mn CPUs are more fragile to Vcore....but what I need to add, is that they are alse sensetive to too much VTT voltage as well...you shouldn't need more that 1.25V anyway.

• I’m just real anxious about permanently toasting something (don’t like throwing $120 away) – keeping a close eye to make sure CPU temps don’t get above 65DegC. Can things get only somewhat damaged and not show up in definite ways until you go back to old/known good settings and find Prime95 is no longer stable or the CPU is running hotter than it used to? Or is it more burnt/not?
It is not uncommon for CPUs to become "degraded" as opposed to just flat dying. But usually these bad things happen a bit closer to the limit. Although there is risk in ANY overclocking, IMHO the bennefit outweighs it by a mile :thup:

Bruce....a lot of good questions and suggestions. If you have more, screenshots would be helpful, and if you create a new thread in this Intel CPU's section, more people will check it and be able to assist. I'm a little rough around the edges with Asus boards, so the additional community support would probably be benneficial, thanks :)
 
core I5 750 + Intel DH55HC mobo

hi ... excellent article , i need help in my case as i have Intel motherboard and there is not much scope of over-clocking as i have learned ...pl assist as to what can i do to maximize performance.

I am also facing a weird problem, my computer hangs and slows badly while multitasking having a quad core processor . I have checking my CPU usage while running processes which is normal . Tried on XP and Windows 7 and it was a nogo ..please help someone !! . Here are my specs.
 
Hello madyville, and welcome to OCF! :welcome:

To best assist you, I'd recommend starting your own thread rather than tacking this on to the end of this one. It seems you have issues that need to be addressed before you begin attempting to overclock.

I'd recommend starting in the Microsoft Operating Systems area. If it's determined to be hardware instead of software, it can be moved to the appropriate section. Be sure to list the applications and background tasks you have running when you experience the hangs. Best of luck!
 
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