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i7 OC Help

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EricM

New Member
Joined
Mar 13, 2009
Hello,

I am new to OC, so please be patient. I recently set up a new rig for myself and I am trying to do some OC. Here is my current set up (please don't say I should have gotten other hardware, because I got a great deal on what I have):

Intel i7 940
Intel DX58SO MB
RAM Corsair 3 X 2GB (6GB) TR3X6G1600C8D
Noctua NH-U12P SE1366 (and multiple other fans in case)
Vista Ultimate 64 bit

I would like to get to at least 4.0 on air, possible?
My temps right now are between 70-75C degrees running Prime95. I attached a few pictures of my settings. Can anyone tell me where I should make adjustments. I am getting kinda confused with the changes. Any help is appreciated. Thank you.


Okay, my pictures sizes are too big for upload, so here goes with my settings:

Clock Frequency: 185
Turbo boost disabled
multilplier: 21
Speed 3.89
Qpi data rate: 6.669

Voltages
memory: 1.66
QPI/Processor uncore 1.35
IOH Core 1.10

Processor Overrides:
Dynamic CPU Voltage Offset (mV) 128
100% slope
Multiplier 21
High performance Idle state

Memory Configurations
Uncore multiplier 17
Memory Multiplier 8
The rest of memory settings are from Corsair website
memory voltage 1.66
QPI/uncore voltage override 1.350
Command rate 2T

Bus Overrides
Ioh core overrides 1.100
QPI Data Rate 4.8

I think that covers the setting I have or can partially change. Anyone see anything wrong or that should be changed?


Eric
 
Might want to post this thread in the motherboard section as well since it has to do with the board/bios . There is a ton of OC stuff in the 1366 section... 4G should be no problem
 
First of all, change that Ram to 1T :p

What do you do with this setup? I wouldn't let the CPU reach over 80C so maybe consider better cooling.

Either way, there are two ways you can overclock.
You can lower the multiplier and then focus on raising the bclk until you hit a wall (as in no voltage up to 1.4V will work) and then use the highest bclk that is stable and focus on raising the multipliers for getting up to 4Ghz. Main voltages you will need to keep an eye on are the CPU and QPI, for the CPU I would think the maximum for 4ghz will be 1.42V, and QPI up to 1.4V.

Otherwise you can just start by increasing the bclk straight away, checking with short runs of prime95 so you don't need to wait ages :p
If it fails in a short time, you bump up the cpu voltage to see if that helps, then the QPI voltage until it is stable, then start increasing it bit by bit until you reach a desired overclock or you have too high temps/voltage.

If you have any trouble, PLL can help an unstable overclock, I have mine set to 1.88V.
Clock skews also help once you have your final overclock to reduce voltages or get that bit more out of the cpu. Just keep an eye on temps (Coretemp, Realtemp are good) whilst using prime95. When you get to your highest clock speed you want, I suggest running prime95 for 8 hours or more. Try and keep QPI under 7.5Ghz, memory kept under or at rated speeds until you reach your overclock for now, then you can focus on getting that higher after otherwise changing too many variables can make it confusing on what you need to adjust.
 
First of all, change that Ram to 1T :p

What do you do with this setup? I wouldn't let the CPU reach over 80C so maybe consider better cooling.

Either way, there are two ways you can overclock.
You can lower the multiplier and then focus on raising the bclk until you hit a wall (as in no voltage up to 1.4V will work) and then use the highest bclk that is stable and focus on raising the multipliers for getting up to 4Ghz. Main voltages you will need to keep an eye on are the CPU and QPI, for the CPU I would think the maximum for 4ghz will be 1.42V, and QPI up to 1.4V.

Otherwise you can just start by increasing the bclk straight away, checking with short runs of prime95 so you don't need to wait ages :p
If it fails in a short time, you bump up the cpu voltage to see if that helps, then the QPI voltage until it is stable, then start increasing it bit by bit until you reach a desired overclock or you have too high temps/voltage.

If you have any trouble, PLL can help an unstable overclock, I have mine set to 1.88V.
Clock skews also help once you have your final overclock to reduce voltages or get that bit more out of the cpu. Just keep an eye on temps (Coretemp, Realtemp are good) whilst using prime95. When you get to your highest clock speed you want, I suggest running prime95 for 8 hours or more. Try and keep QPI under 7.5Ghz, memory kept under or at rated speeds until you reach your overclock for now, then you can focus on getting that higher after otherwise changing too many variables can make it confusing on what you need to adjust.

Thank you for the info. I will give those settings a try. The one thing I just changed right now was the RAM to 1T. The computer seems stable right now with no other changes @ 3.9. I just ran Prime95 for an hour. Maybe I will stick with not going to 4.0, I don't know. It's funny how my core #4 is about 5 degrees C cooler than the others. I might have to try and redo the thermal paste.
 
It's funny how my core #4 is about 5 degrees C cooler than the others. I might have to try and redo the thermal paste.

My CPU is the same way #4 is cooler by a few degrees. I think that may be the norm with this I7. I've seen a few others note that too.
 
My Core 3 and 0 are 2C below 1 and 2, which are equal. Must be to do with the fitting of the cooler, or just because the center cores are surrounded by heat?

The 1T will just help the bandwitdh a bit, and tighter timings can help very slightly in games. I know how you feel, I didn't overclock seriously for a month on my cpu before I got round to it :p
 
Okay, here are my settings so far (Hardware mentioned above). I can get windows to boot, but once it starts, the computer freezes shortly after. What do you think? Do I need to increase the voltage, or do something else? i do have the Turbo off for right now.

Just a reminder, I have limited changes available for the mobo is Intel DX58SO, chip is i7 940

Clock frequency 200
Non turbo multiplier 20
CPU voltage offset (mV) 128
Uncore multiplier 17
Memory Multiplier 8
Memory voltage 1.66 v
QPI / Uncore voltage override 1.35 v
IOH core voltage override 1.100 v
QPI data rate 4.8 GT/s

These settings show me at a speed of 4.00 GHz, memory speed of 1601 MHz and QPI data rate of 7.205. It is obviously not stable because it crashes if any load is applied when in windows.

What do you think should be changes? Any help is greatly appreciated. Thanks

Eric
 
Okay, Here are the new settings. Temps fluctuating between 70-77 C running Prime95 after 30 minutes (going to run it for a few hours tomorrow)

Clock frequency 190
Non turbo multiplier 21
CPU voltage offset (mV) 128
Uncore multiplier 17
Memory Multiplier 8
Memory voltage 1.66 v
QPI / Uncore voltage override 1.35 v
IOH core voltage override 1.100 v

Turbo off

CPU = 4.00 (3996) GHZ
Memory = 1522 MHz
QPI data rate = 6.851 GT/s

What do you think?
 
So what is actual CPU voltage? Fire up CPU-z whilst running prime for the cpu volts as you might have power saving options /vdroop on.

Looks good, I was going to say odd multipliers generally are better :p
Hopefully that is stable, as the settings look good enough for it to be from what I see. You might even be able to get a bit more out of her if it is.
 
So what is actual CPU voltage? Fire up CPU-z whilst running prime for the cpu volts as you might have power saving options /vdroop on.

Looks good, I was going to say odd multipliers generally are better :p
Hopefully that is stable, as the settings look good enough for it to be from what I see. You might even be able to get a bit more out of her if it is.

Running Prime right now and CPU-Z says core voltage is 1.324 V
It is at 1.348, at idle (I think I have performance settings at idle in BIOS)
 
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Okay, 190 X 21 is the highest I can go without a crash (so far). 191 crashed. Now, I have the memory multiplier set at 8 and uncore multiplier set at 17. How high should the Uncore multiplier be set at? I am unsure what this setting does. The only thing I remember reading was it should at least be set to 2x+1, which is what I have it at. What will it do if I raise it more and should I?
 
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