i7 920 overclocking thread

[CDMAN]

Originally Posted by XFreeRollerX

That picture is horrible dude post it in a better res. I cant read anything on CPUZ

I will take some better pics when I get off of work. Also If you stay at 1.45 volts for the core, and 1.65 for the Dimms you will be fine. Here is some info to help you out.

How to find max Bclock:
Bclock 133Mhz
CPU Multiplier 12x/14x
Uncore Multiplier 16x or higher
QPI Multiplier 18x
Memory Multiplier 8x or lower
Vcore 1.25v
VTT 1.45v
Vdimm 1.65v

push up the Bclock and increase VTT and QPI volts to get higher.
Max 100% safe VTT seems to be 1.65v


How to find max Mem clock:
Bclock 133Mhz
CPU Multiplier 12x/14x
Uncore Multiplier 16x or higher
QPI Multiplier 18x
Highest Memory Multiplier
Vcore 1.25v
VTT 1.45v
Vdimm 1.65v

push up the Bclock and increase VTT and Vdimm to get higher.
more vdimm and vtt than 1.65v at your own risk
1.8vdimm should be 100% safe though

How to find max CPU Clocks on i7-940/i7-920:
max Bclock
CPU Multiplier 15x
Uncore Multiplier 16x or higher
QPI Multiplier 18x
Memory Multiplier 8x or lower
Vcore 1.25v
VTT 1.45v
Vdimm 1.65v

increase CPU multipliers step by step, push up vcore to get higher clocks stable. if you cant get a multiplier stable, reduce Bclock until your stable.
Max bclock for high multis is slightly lower than for low multis.

[{core2duo}werd]

Originally Posted by gooddog

Careful on voltage.
The new max is NOT really 1.55. That is the absolute max voltage. See quote below.

It is around 1.375.

1.55 is the voltage after which you may not recover, even when you drop the voltage below 1.375 again.

From the PDF
http://download.intel.com/design/pro...hts/320834.pdf

it says that 1.55 is the absolute max, and i wouldn't push it that high, but it doe NOT say that 1.375 is the maximum safest voltage.

edit maybe you are confused because it says the max vid is 1.375. that is the max stock voltage they will make a chip with, and there is always room above that for overclocking.

[mr.derp]

Im liking nehelem a lot, but Im willing to wait for AM3 to come around because I want to see if it competes at all before I buy anything. I think these overclocks are pretty sweet and it would be even sweeter if the max voltage is 1.55.

[error10]

Originally Posted by CDMAN

Nice work man. I was thinking of going to water cooling, but I see that your temps are just about what I have at 4.1 so I may hold off if I done need to. I will take a reading tonight at 4.4 to see what my temps are.

You probably need to reseat your HSF. You shouldn't have hit PROCHOT# during your bench. (That means your CPU temp exceeded Tjmax.)

[{core2duo}werd]

Originally Posted by error10

You probably need to reseat your HSF. You shouldn't have hit PROCHOT# during your bench. (That means your CPU temp exceeded Tjmax.)

yeah, WOAH those are idle temps. mine were load.

[CDMAN]

Yeah, I know. Once I get my mounting kit this afternoon, I will reseat the HSF.

[gooddog]

Originally Posted by {core2duo}werd

it says that 1.55 is the absolute max, and i wouldn't push it that high, but it doe NOT say that 1.375 is the maximum safest voltage.

edit maybe you are confused because it says the max vid is 1.375. that is the max stock voltage they will make a chip with, and there is always room above that for overclocking.

That's the problem - open to interpretation.

I think the key phrase is:

At conditions outside functional operation condition limits but within absolute maximum and minimum ratings, neither functionality nor long-term reliability can be expected.

I take 1.375 as the functional operation condition limits, and 1.55 as the max ratings.

So I read this as 1.375 as max safe.

[error10]

Originally Posted by CDMAN

Yeah, I know. Once I get my mounting kit this afternoon, I will reseat the HSF.

Don't forget to re-bench, too. When your CPU runs that hot it automatically downclocks itself to as low as 12.5% of its speed. (Unless you disabled that feature in BIOS, on the advice of some OCer, but that seems like a good way to fry your chip.)

[zlojack]

Originally Posted by gooddog

That's the problem - open to interpretation.

I think the key phrase is:



I take 1.375 as the functional operation condition limits, and 1.55 as the max ratings.

So I read this as 1.375 as max safe.

Where do you get 1.375 from?

The VID range?

[gooddog]

Originally Posted by zlojack

Where do you get 1.375 from?

The VID range?

From the same pdf. Table 2.7. It is the VID range.

Again, I can be wrong, but I am sure that 1.55 is not the safe voltage.