LGA1156 Core i7 & i5 Overclocking Guide

[sxr7171]

NM

 

[The Sauce]

Thanks for the extremely useful guide. Please sticky! It prompted me to upgrade now. I was reluctant to upgrade because i was intimidated by learning all the new settings, voltages and myriad other things that I had not kept up with over the past few years. This guide decreased my research time considerably. Building the new system now.

I think you should leave the guide alone and include the recommendations. As an i5 noob I found them very helpful in making quick purchasing decisions. I bought the HS you recommended (Megahalems) and was not really interested in doing tons of research on my own. Also, I really like the debates - LLC, EIST, etc. They helped me to learn a lot that I need to know before I start my overclock. Bring on more debates!

Now I have a retarded question which has likely been discussed a thousand times already, but here it goes. I understand turning off Turbo for overclocking. But leave it off? Is an overclocked 750 with turbo off faster, in general, than a stock 750 with turbo on?

 

[andy5174]

I understand turning off Turbo for overclocking. But leave it off? Is an overclocked 750 with turbo off faster, in general, than a stock 750 with turbo on?

The Maximum turbo with 1 or 2 cores active gives 3.20GHz, so you will definitely get better performance all the time with any OC greater than 3.20GHz.

http://processorfinder.intel.com/details.aspx?sSpec=SLBLC

UPDATE: By the way, you might be able to leave turbo mode on with 3.0GHz OC.

 

[The Sauce]

My initial attempt at overclocking this thing is a rousing success. The odd thing is that I did not find any option in the BIOS to turn on or off Turbo Mode. I assume just the act of changing the FSB speed disables Turbo?

So, to use the format of your guide:

4.1 Ghz (21 x 195)
LLC: Enabled
Vcore: 1.35
QPI/IMC: 1.4
PCH: 1.1
PLL: 1.9

 

[andy5174]

My initial attempt at overclocking this thing is a rousing success. The odd thing is that I did not find any option in the BIOS to turn on or off Turbo Mode. I assume just the act of changing the FSB speed disables Turbo?

So, to use the format of your guide:

4.1 Ghz (21 x 195)
LLC: Enabled
Vcore: 1.35
QPI/IMC: 1.4
PCH: 1.1
PLL: 1.9

You have to MANUALLY turn off the Turbo Mode with DEFAULT multiplier(20x). However, Turbo Mode is automatically turned off on i5-750 and i7-860 with 21x and 22x multiplier respectively.

p.s. I will be really appreciated if you can post the result of your voltages after stability test, because I can then replaced the insufficiently tested values provided by me with them.

 

[The Sauce]

Even when I had the multi at 20 I did not see an option for disabling Turbo.

 

[andy5174]

Even when I had the multi at 20 I did not see an option for disabling Turbo.

What is your motherboard? Have you checked the manual?

 

[The Sauce]

Oh I got it, nvm. I have an ASUS P7P55D and it automatically disables Turbo when CPU Ratio Setting is anything other than "Auto" Even typing in 20 manually will disable it, apparently. That explains it.

I'll keep my settings updated here for you as I overclock higher.

 

[MrK6]

Why again are we disabling turbo? You'll want to force the 21x multiplier if you're going for maximum overclocks.

 

[The Sauce]

Final stable o/c numbers (i5 750, P7P55D, Megahalems):

4.2 @ 1.325v - temps low-mid 60s
4.3-4.35 @ 1.4v - temps mid 70s
4.4 @ 1.425 - temps upper 70s - low 80s

Stopped because of temps hitting low 80's.

LLC: Enabled
Vcore: 1.35
QPI/IMC: 1.2
PCH: 1.1
PLL: 1.9

 

[The Sauce]

For anyone who is interested I think this may be a good stepping/batch. I haven't seen people hitting these speeds/temps/volts even with water yet. Bought the chip from Newegg on 1/20/10.

Prod Code: BX8060515750
MM#: 903877
FPO/Batch#: L934B414
S-spec: SLBLC Malay

 

[Parsa]

Hi

my mainboard is Asus P7P55D Deluxe And my CPU Is 860 ....

I Want To Overclock This system With This Profile :

BCLK Clock : 200

CPU Multiplier : 20 or Any Multipliers

DDR : 1600 Timing 7-7-7-20


I Things 200 Mhz Is Max BCLK Clock For 24/7 !

In Your Opinion Frequency 200 Is Safe For 24/7 ??!!

If No What Frequency Is safe For 24/7 ?

 

[andy5174]

Hi

my mainboard is Asus P7P55D Deluxe And my CPU Is 860 ....

I Want To Overclock This system With This Profile :

BCLK Clock : 200

CPU Multiplier : 20 or Any Multipliers

DDR : 1600 Timing 7-7-7-20


I Things 200 Mhz Is Max BCLK Clock For 24/7 !

In Your Opinion Frequency 200 Is Safe For 24/7 ??!!

If No What Frequency Is safe For 24/7 ?

It really depends on your chip and cooling solution.

It is safe as long as both of the core temperature and core voltage are within the maximum specification by Intel.

 

[Parsa]

It really depends on your chip and cooling solution.

It is safe as long as both of the core temperature and core voltage are within the maximum specification by Intel.

Thank You

So If Voltage Is Down Of The 1.40v And Temp Is Down Of the 60 º C ( Pc Probe Use For monitoring Temp ) .. You Think No Problem ?

I thing If Voltage Lower Than 1.40 and Temp Lower Than 60 or 55 º C No Problem For 200x22 If Possible This Setting For Stability ...

No Problem If Not Possible Becouse I will Use 200x21 Or 20 That Possible it .

So No Problems For 200x20 ( For Example ) 1.3750v Or Lower and Temp Lower Than 60 º C ?

Thank You Very Much .

 

[AkumaX]

bump

 

[aggressor]

So I'm at 171x21 right now, using a CPU vcore of 1.25, VTT of 1.1625, and VDimm of 1.65.

With this, I'm stable, but for the life of me I cannot seem to get the CPU clock higher. I can get the uncore speed up to 185mhz and be stable as long as I drop the CPU multiplier, but with any higher CPU frequency I get errors in Prime 95 and IntelBurnTest (which manages to get my cpu 5c higher than Prime95, btw).

Anyone have any ideas? My motherboard is the Asus P7P55D-E and it has a lot of tweak settings, but I have no idea what they really do.

 

[andy5174]

So I'm at 171x21 right now, using a CPU vcore of 1.25, 1. VTT of 1.625, and VDimm of 1.65.

With this, I'm stable, but for the life of me I cannot seem to get the CPU clock higher. 2. I can get the uncore speed up to 185mhz and be stable as long as I drop the CPU multiplier, but with any higher CPU frequency I get errors in Prime 95 and IntelBurnTest (which manages to get my cpu 5c higher than Prime95, btw).

Anyone have any ideas? 3. My motherboard is the Asus P7P55D-E and it has a lot of tweak settings, but I have no idea what they really do.

1. Did you read the guide? The max and absolute max Vtt are 1.155V and 1.21V respectively. Your Vtt is way above the absolute max and you are asking for trouble.

2. Follow the guide STEP BY STEP! You are an EXTREMELY unlucky owner of the worst chip if you still can't achieve 185x20=3.7GHz. BTW, I haven't heard anyone who want to achieve 4.2GHz on i5-750 but failed so far.

3. Guides can only give you ideas on how to OC. You have to take time and read the manual to learn how to achieve the steps shown in guides!

 

[andy5174]

Thank You

So If Voltage Is Down Of The 1.40v And Temp Is Down Of the 60 º C ( Pc Probe Use For monitoring Temp ) .. You Think No Problem ?

I thing If Voltage Lower Than 1.40 and Temp Lower Than 60 or 55 º C No Problem For 200x22 If Possible This Setting For Stability ...

No Problem If Not Possible Becouse I will Use 200x21 Or 20 That Possible it .

So No Problems For 200x20 ( For Example ) 1.3750v Or Lower and Temp Lower Than 60 º C ?

Thank You Very Much .

You will be fine as long as all voltages and temps are within the following spec!

(LGA1156 CPU Maximum/absolute Maximum voltage by Intel: Vcore= 1.40/1.55, Vtt= 1.155/1.21, Vram= 1.575/1.65, PLL= 1.89/1.98, PCH=1.10, max temp 72.7C)

 

[aggressor]

Whoops, sorry, I mistyped the VTT voltage. It's at 1.1625.
The more I think about it, the more I think it's just my cooler. Temps hit 75c when at 3.6ghz according to RealTemp. The cooler isn't the best (CoolMaster Hyper 212) but I thought I could at least do 3.8ghz, which was my original goal.

 

[andy5174]

Whoops, sorry, I mistyped the VTT voltage. It's at 1.1625.
The more I think about it, the more I think it's just my cooler. Temps hit 75c when at 3.6ghz according to RealTemp. The cooler isn't the best (CoolMaster Hyper 212) but I thought I could at least do 3.8ghz, which was my original goal.

Did you make sure that the cooler is well fastened onto the MB? What is your ambient temperature? You need a better cooler if ambient temperature at any time exceeds 30C A N D you are at full load most of the time.

p.s. The core temps of my i5-750@3.6GHz are 48C-44C-44C-41C under 17C ambient with Prolimatech Megashadow. In addition, they should increase to 61C-57C-57C-54C under 30C ambient. Hence, I expect core temps to reach 70C(which is very close to the max, 72.7C) under 30C ambient with hyper 212 plus.

 

[aggressor]

It's 63f\17c here right now, so I don't think that's it. My temps don't seem all that out of place according to reviews, particularly this one: http://www.pureoverclock.com/review.php?id=826&page=7

He's hitting 77c at at 3.8ghz, but his ambient temperatures are a bit higher. I think I'll pull off the heatsink and reapply the thermal paste to see if that helps any.

Edit: and I don't think Prime95 is a good way to test maximum temp. IntelBurnTest gets my CPU much more toasty even when using the Maximum Heat setting in Prime95. Have you tried it?

 

[andy5174]

That's a good idea!

75C is just insane under 17C with Hyper 212 Plus.

Update: Yes, I have tried IBT as well and the core temps is just 4~5C higher. BTW, I just passed 20 runs IBT test 2 days ago.

 

[aggressor]

I'm not a huge fan of this heatsink's design. This is what I got when I pulled it off:

www.aggybong.com/temp/cpu.jpg
www.aggybong.com/temp/heatsink.jpg

All of the creases in the heatsink make it hard to properly spread thermal paste around. I added a...liberal amount of AS Ceramique now. I didn't pull it off to verify it was covering more of the heatsink, but I can do that in a bit after some testing.

 

[andy5174]

I'm not a huge fan of this heatsink's design. This is what I got when I pulled it off:

www.aggybong.com/temp/cpu.jpg
www.aggybong.com/temp/heatsink.jpg

All of the creases in the heatsink make it hard to properly spread thermal paste around. I added a...liberal amount of AS Ceramique now. I didn't pull it off to verify it was covering more of the heatsink, but I can do that in a bit after some testing.

That's a terrible job. Clean it with industrial alcohol!

Application method:

Result:

 

[aggressor]

Disabling HT (yes, I had that enabled. I knew about the added heat gain from it) = from 80c max to 70c max
Redoing the thermal paste = from 70c to 68c

Getting better, but still not all too great.

Edit: I should add that those are from IntelBurnTest and for the hottest core only. If I use Prime95, it's 64c max.