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cpu vtt voltage

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jimijames

Member
Joined
Oct 23, 2008
I was reading an overclocking guide for the core i7 930's and its said the cpu vtt voltage needs to be set at 1.45, when i go into my bios i can choose between 125 and 150 should i set it to 150 or am i lookin in the wrong place perhaps?
 
its an evga classified motherboard, havent had any real luck gettin it stable at 4.5, yesterday all i did was set the multiplier to 21 and the bclk to 215 and i set the vcore from 1.40 to 1.5 and couldnt get a stable o/c. those are the only things i have messed around with. did some more reading today but not sure what all the other settings need to be set at
 
1.5v? What cooling? Thats a bit much for 24/7 operation...

Please list system specs so we know what we are dealing with...
 
my system is watercooled the temp was peaking at about 71 at 1.5 volts. my systems specs are
evga classified mobo
i7 930 D0 stepping
swiftech apogee xt waterblock
swiftech mcp655 pump
6gigs ddr3 2000 supertalent mem
ocz 850 watt psu
ati 4890 video card.
s/b n/b are watercooled as well

i currently have my pc overlocked to 4189 ghz with a vcore of 1.329. it runs slightly sluggish tho temps are maxing out around 41 degrees
 
ok so i think i almost have my system stable. i was able to run occt for about 40 mins before recieving a bsod. when i restarted windows the bccode was d1 what does this mean and what in the bios setting should i change if any? my current bios settings are as follows

cpu host frequency 201
cpu clock ratio 21
cpu vcore 1.33750
cpu vtt =200mv

memory frequency 1333mhz
8--8-8-24 at 2t
dimm voltage 1.66

i had the uncore set to auto
temps were between 58 and 61,in coretemp, the whole time. the temps on my motherboard LED never went past 45 degrees
any help would be greatly apreciated
 
D1 should be in your manual, Im not sure...sorry.

Keep going on your testing...add a voltage one thing at a time and retest.
 
is there a way to pull up old bsod info in vista? nvm i found out how to do it
 
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Product
Windows

Problem
Shut down unexpectedly

Date
1/28/2011 2:09 PM

Status
Not Reported

Problem signature
Problem Event Name: BlueScreen
OS Version: 6.0.6002.2.2.0.768.3
Locale ID: 1033

Files that help describe the problem (some files may no longer be available)
Mini012811-04.dmp
sysdata.xml
Version.txt

Extra information about the problem
BCCode: d1
BCP1: 0000000000000000
BCP2: 0000000000000002
BCP3: 0000000000000000
BCP4: FFFFFA8005347520
OS Version: 6_0_6002
Service Pack: 2_0
Product: 768_1

checked my mobo manual and doesnt seem to have d1 in the error codes

that is the info from the bsod any thoughts?
 
Alrighty, so i was able to complete the occt hour test without any errors. my temps briefly peaked at 61 degress then would drop back to between 58 and 60 through out the hour. here are my final bios settings

Cpu Clock Ratio: 21
Cpu Host frequency: 201
Cpu uncore: 4026
Cpu Vcore: 1.3375
Cpu Vtt: +225 mV

Memory 1333 Mhz (2:10
target mem Frequency: 2013
channel interleave: 6 way
Rank interleave: 4 way
8-8-8-24 2t
Dimm Voltage 1.66volts

Qpi linkfast enabled
qpi selection auto

a few questions will the qpi and uncore frequencies help my system run any faster and if so which voltages correlate to them if i want to try to set them higher.

Secondly do i have the headroom to go to 4.5ghz? any thoughts would be greatly apreciated thx again this site has been very helpfull in helpling me get this thing o/ced
 
a few questions will the qpi and uncore frequencies help my system run any faster and if so which voltages correlate to them if i want to try to set them higher.

Secondly do i have the headroom to go to 4.5ghz? any thoughts would be greatly apreciated thx again this site has been very helpfull in helpling me get this thing o/ced

You have a decent uncore speed going there, no need to push past 2X the DRAM speed. VTT will allow for higher Uncore. Any increases in Uncore will go almost entirely unnoticed for everyday use. There are definite benchmarking benefits to increased uncore speeds though.
QPI... you can't change it.
As far as headroom for 4.5, it appears to be within your cooling capacity, but honestly 4.5 on a 930 is pushing it as a daily stable rig. It all depends on your definition of stable though ;) If it was a 920, I would say more than likely it could do it, but not the 930.
 
i wont be doin any benching on this p/c. i do want to try to get it stable at 4.5ghz tho becuase i want to xfire a couple of 6990 when they come out. this machine is mostly for gamming for about 3 to four hours in the evening. i didnt think there was much diffrence between a 920 and 930. i thought the 930's were slightly better o/cers. this chip has D0 steppin on it if that helps at all
 
i didnt think there was much diffrence between a 920 and 930. i thought the 930's were slightly better o/cers. this chip has D0 steppin on it if that helps at all

Actually it's the other way around. Historically the 920 D0's will usually outperform their 930 counterparts. Just a bit of speculation on my part but, with the wild success of the 920 D0 stepping, I think Intel realized they needed to start binning their CPU's a little bit better. The move to the 930/950/960 lineup allowed them to do that.
If 4.5 is your goal, then give it a shot. I'm betting that you'll need to be below ambient temps, but you'll never know if you don't try :thup:
 
well darn, i originally had a 920. what temperature do i not want to exceed at at 4.5?
 
Whatever temperature you want. Most people don't want to go over 85 on any core when doing, say, Linx at 25000 problem size. During gaming, you'll never reach that load and temperature.

By the way, which Classy do you have? If it's an older one, base Vtt was 1.1 V. The newer ones have a base Vtt of 1.2 V. If you have a newer one, +225 would bring it to 1.425, just at the edge of what I would recommend (1.45) since it's 0.075 over Intel's spec of 1.35. Verify with a multimeter if you must.
 
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i have a 3x sli classiffied, i believe its one of the older boards. i think i will wait till i can get my hands on a pair of 6990 and see if i need more horsepower to run them
 
So i have ran into a new problem it seems. when my pc goes through its posting procedure it only read 4 gigs of ram, when i open up windows task manager it is only seeing four gigs of ram. when i open up cpu-z it says i have six gigs of ram. Could the memory controller on my cpu be damaged? or possibly something wrong with my motherboard? i switched out the memory to a different six gig kit and it still read as four gigs so i dont believe it is the memory moduals. any thoughts?
 
QPI... you can't change it.

You can't? I swear I remember lowering the QPI multi on the recent 920 rig I built for a friend.

A few Google hits shows 18x, 20x, and 22x QPI multi's available. Are we discussing 2 different things here?


So i have ran into a new problem it seems. when my pc goes through its posting procedure it only read 4 gigs of ram, when i open up windows task manager it is only seeing four gigs of ram. when i open up cpu-z it says i have six gigs of ram. Could the memory controller on my cpu be damaged? or possibly something wrong with my motherboard? i switched out the memory to a different six gig kit and it still read as four gigs so i dont believe it is the memory moduals. any thoughts?

Not damaged, but being pushed too far, currently. It is possible that the IMC has degraded some due to slightly excessive voltage (electromigration), but it should still work just fine if you back off a bit. Reduce your RAM multi, and make sure your uncore is twice your RAM speed. You could try increasing VTT, but you have it pretty high already. I would just shoot for the next RAM speed down, and tighten your timings up a bit to help make up the difference.

I was hoping to run 200x21 w/ 10x RAM multi (DDR3-2000) in tri-channel on the 920-D0 rig I built recently for a friend. It was just taking way too much vtt compared to the 8x RAM multi and the performance difference was negligible. Plus temps were higher, and 100% stability was just about impossible to attain (taking too long for my friend to wait anyway).

You can run the RAM faster w/ only dual-channel as opposed to tri-channel. Your rig is doing that on its own for you. It's either drop to dual-channel or not POST.
 
hmmmm....if i was to go with one of the higher core i7 cpu's would that solve the problem? these moduales are rated to run at 2000mhz. i was thinking about a core i7 950
 
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