Trying to hit 4.1GHz with an i7

[michaelmk86]

Hi

I have an i7 at 3.8GHz stable for about 2 years, last week I decided to OC further to 4.1GHz and turn the HT off for easier OC to 4.1. Now every time I turn on my pc it doesn't post and I have to press restart in order to boot normally with my OC at 4.1 and it is also prime95 stable and play my games normally without any problems. The only thing that i did was to turn the HT off and set Base clock from 181 to 195, and the Vcore from 1.24v to 1.293v.


my settings

cpu - i7 920 D0
mobo - ASUS P6T

4095 MHz
Base clock to 195
Vcore to 1.293v
Mem divider set to 1560
9-9-9-24
QPI/VTT auto
HT off
Turbo enabled
prime95 max temp 66C


everything else is default/auto

 

[Rifter]

i would take VTT off auto and just use whatever voltage you need to keep it stable. I experienced some boot issues with my i7@4.2 till i manually set the VTT, i also needed 1.35V VTT to stay stable above 4Ghz.

 

[michaelmk86]

Thanks for the advise VTT on auto seem to be the problem.

I set the VTT to 1.293v the same like the Vcore and now the pc start normally, and it is prime95 stable and also with 2C lower temp than the "auto".

 

[Suspicious-Teach8788]

never use auto if you're doign some tweaking.

i'd also recommend doing Linx or intel burn test and not Prime 95. 1.293V means you have a very good chip. It takes me 1.35V to hit 4.1ghz. I'm at 1.33 running 4.01.

 

[michaelmk86]

never use auto if you're doign some tweaking.

i'd also recommend doing Linx or intel burn test and not Prime 95. 1.293V means you have a very good chip. It takes me 1.35V to hit 4.1ghz. I'm at 1.33 running 4.01.

Cool i didn't known that intel burn test was better than Prime95, it is still requires to run intelburn for hours like the Prime or it can detect any errors in a few minutes?

I don't really think that i have a good chip because i have HT off, with HT on i will probably need more voltage.

 

[LiuKangBakinPie]

Hi

I have an i7 at 3.8GHz stable for about 2 years, last week I decided to OC further to 4.1GHz and turn the HT off for easier OC to 4.1. Now every time I turn on my pc it doesn't post and I have to press restart in order to boot normally with my OC at 4.1 and it is also prime95 stable and play my games normally without any problems. The only thing that i did was to turn the HT off and set Base clock from 181 to 195, and the Vcore from 1.24v to 1.293v.


my settings

cpu - i7 920 D0
mobo - ASUS P6T

4095 MHz
Base clock to 195
Vcore to 1.293v
Mem divider set to 1560
9-9-9-24
QPI/VTT auto
HT off
Turbo enabled
prime95 max temp 66C


everything else is default/auto

can you post the following values
Cpu frequency = bclock x CPU clock ratio

QPI frequency = bclock x QPI clock ratio

Uncore frequency = bclock x uncore clock ratio

Memory frequency = bclock x System Memory Multiplier (SPD)

CPU Vcore
QPI/VTT voltage

Then did you do the following?
Isolate the bclock from the CPU
Isolate the bclock from the memory
Lock in your desired uncore clock ratio

 

[Suspicious-Teach8788]

Cool i didn't known that intel burn test was better than Prime95, it is still requires to run intelburn for hours like the Prime or it can detect any errors in a few minutes?

I don't really think that i have a good chip because i have HT off, with HT on i will probably need more voltage.

HT Off helps a lot. I have some data somewhere showing that HT Off gives me like a 50mhz boost or something (just a quick estimate)

I think IBT or LinX stresses more than Prime 95 in my opinion. Errors? I don't know. I've heard reports both ways that sometimes Prime errors first, sometimes LinX errors first, but I think most people on XtremeSystems will agree that Linpack tests are more stressful.

I myself like to use OCCT. They have a Linpack test that seems to stress my system well and it errors rather quickly. Prime95... eh. I don't really bother. I think it's too easy to pass.

 

[michaelmk86]

Actually setting the VTT from auto to 1.293v didn't help (i thought that this was the problem because one time it boot normally).

@LiuKangBakinPie what do you meant "Isolate the bclock from the CPU" and "Isolate the bclock from the memory"?

 

[itsmydamnation]

Bclock + mem multi = mem speed. he is saying make sure that your not pushing your memery to hard ,ie change the divider down ( on X58 it doesn't matter any way cuz of tri channel you have so much bandwidth)

for me either my CPU or my MB hit a bclock wall around 190, which sux. But because i have a C0 it doesn't matter to much because at that speed full load on all cores i will hit 100C......

onyl way i could see to isolate the bclock from the CPU is to run a higher multi, but your limited in that regard on a 920 so its not really an option.

 

[michaelmk86]

Bclock + mem multi = mem speed. he is saying make sure that your not pushing your memery to hard ,ie change the divider down ( on X58 it doesn't matter any way cuz of tri channel you have so much bandwidth)

But i already have my memory underclock to 1560MHz(9-9-9-24), the stock frequency for my memory is 1600MHz(9-9-9-24).