Can't get i7 920 stable

[TJ Tom]

I finally assembled my watercooling loop so I can overclock this i7 920. Before I go any further, note that I am dealing with a C0/C1 stepping.

I started out with 4GHz as my main goal and after days of playing with voltage settings and stress test software I got my system "stable" at 4GHz.

I was running 4GHz with x20 multi, 200MHz BCLK with following voltages:
- Vcore: 1.4V
- QPI/VTT: 1.36V
- PLL: 1.8V

My 1333MHz memory was running with a x6 multi @ 1200MHz with 1.5V (stock)

I ran OCCT for 9 hours (no error) I was able to run Prime95 for several hours and InetlBurnTest passes over 15 loops without an error (usually when a setting is too low (Vcore for example) IBT fails within 5 loops.)

So... thinking I got my i7 stable at 4GHz I started up BFBC2 to play some rounds and within 30 minutes it reboots on me with the 0x124 code.

Some research quickly made clear I had to either increase or decrease the QPI/VTT voltage but why didn't OCCT/Prime/IBT give me any error or freez? Is BFBC2 the ultimate stress tester?

I started upping the QPI voltage to 1.4V and decreasing the Vcore and I have adjusted these 2 settings so often I forgot what I tested and what I didn't test.

Result: I now write down all my settings when my computer freezes on me (BSOD).

After a few days I decided 4GHz was not the frequency for my CPU so I settled for 3.8GHz (20 x 190MHz) with 1.375V (Vcore) and 1.34V (QPI)

These settings gave me a BSOD with, again the x124 code so now I am running 3.8GHz with 21 x 181 because a 21 multi is suposed to be more stable. Vcore is at 1.375V (which seems to be enough for everything under 3.9GHz) Uncore (QPI) was at 1.4V.

Again the whole system was stable as a rock (according to Prime, OCCT and IBT) but it crashes on me in BFBC2 with the x124 code. No matter how high I set my Uncore (QPI) it gives me x124 codes. I don't go over 1.4V simply because I don't want to as Intel states 1.35V is the max for the QPI/VTT.

Now, my question to you guys is, what am I missing here? I must be doing something wrong obviously (or this CPU just sucks). Why is it only BFBC2 gives me errors (it doesn't on stock speed so it's not the game itself) and all the other programs seem to think my system is stable.

You are not telling me I can't run 3.8GHz because it can, it runs 9 hours of OCCT at 4GHz so it should be rock solid at 3.8GHz (I think).


Edit:

My QPI Link speed is 6.5GHz (181MHz x 36)
And Uncore frequency is 2353MHz (2.3GHz)

IIRC, QPI/VTT is the amount of volts needed for these 2 frequencies?

Also, I was told that a too high QPI/VTT voltage may have an adverse effect, that's probably why the x124 code suggests increasing (or DEcreasing) the QPI voltage. For that reason the QPI/VTT voltage is now at 1.3V which can't be too much I believe. So if I get another x124 BSOD I am 100% sure it needs more than 1.4V to run 3.8GHz with x21 multi. This seems like a retarded amount of volts for 6.5GHz QPI and 2.3GHz uncore?

Edit 2:

x124 BSOD @ 1.3V QPI/VTT so I turned it up to 1.42V now. Is there something I can do to get a lower QPI/VTT voltage?

 

[redduc900]

Without knowing what model board you have, or the amount of RAM installed, some boards (specifically those made by Asus) require more VTT than other brands. Even though the max. VTTA and VTTD as spec'd by Intel is only 1.35V, some boards require as high as ~1.55V for a stable overclock, depending on the current BCLK, the amount of RAM installed, and the current DRAM frequency. And a 1.375V Vcore seems high for only a 3.8GHz clock, even w/ an older C0 stepping chip. A Vcore of ~1.33-1.35V should be all that's needed at that clock. For a 4.0GHz clock, instead of 200 x 20 try 190 x 21 on the x6 DRAM multiplier, this using the ~1.4V Vcore you were using previously.

 

[TJ Tom]

Sorry, thought I posted everything

I have a Gigabyte X58 UD4P
6GB (3x2GB) Kingston Valueram 1333MHz running with a x6 multi = 1086MHz @ 1.5V

I don't think Vcore is the problem here, but I'm new to this so what do I know. My Vcore is @ 1.375V and QPI/VTT was at 1.42V but it just froze on me 5 minutes ago.

I'm going to see if it still freezes in BFBC2 with a QPI/VT of 1.5V (if it does then I know the x124 BSOD has nothing to do with the QPI/VTT cause 1.5V is crazy high for 3.65GHz with turbo boost to 3.8GHz.

My multi is still at x21 and BCLK is at 181MHz

Next freeze I will set my Vcore back to 1.4V but I seriously hope I don't need 1.4V for 3.65GHz/3.8GHz


EDIT:

Vcore @ 1.375V
QPI/VTT @ 1.5V !!!

= x124 BSOD

I think I can safely say the 0x124 BSOD has nothing to do with the QPI/VTT voltage (atleast in my case) because I have NEVER seen a C0 with 1.5V for QPI/VTT

I have upped the Vcore to 1.425V to see what error I will get now. x124 can only be Vcore or QPI related as far as I know si if I get the 124 error again I'm gonna buy a rope...

 

[redduc900]

Until after you find your max. overclock, disable Turbo, C1E, C3/C6/C7 HALT states, and EIST.

 

[TJ Tom]

I disabled EIST, C3/C6/C7 and C1E but I left Turbo on for the fixed x21 multiplier because it's suposed to be more stable than x20?

All results before were with C1E, SS, EIST, C3/6/7 and Turbo off (4GHz with 200 BCLK) but for 3.8GHz I used Turbo.

 

[TJ Tom]

Another 0x124 BSOD in Battlefield with the following settings:

- 3.8GHz (21 x 181) Turbo mode enabled but all power saving features disabled.
- QPI Link speed 6.5GHz (x36)
- Uncore frequency 2.35 GHz (x13)
- Memory frequency 1086 MHz (x6)

- Vcore = 1.42V
- QPI/VTT = 1.50V
- RAM = Auto (1.54V in EasyTune6)
- PLL = 1.800V


I think Vcore and QPI/VTT are not the problem because both were well over what could have been needed to run at 3.8GHz I believe??

I now disabled Turbo mode and run the following settings:
- Vcore = 1.400V
- QPI/VTT = 1.34V
- CPU/PLL = 1.88V
- RAM = Auto

All other voltages at auto

RAM is running at 1086 MHz still and QPI/Uncore both run at the same speeds. So I just raised PLL to 1.88V and lowered Vcore and QPI/VTT and disabled Turbo mode.

Processor now runs with these settings at 3.6GHz (20 x 181) Sure 1.4V Vcore is enough and 1.34V should also suffice for QPI and Uncore?