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Small FFT stable, Blend Unstable ... Memory Suspect

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JMass

Registered
Joined
Jan 19, 2010
Location
Louisville, KY
I had a previous post in the mobo subforum with
regards to having high Vmch at a certain overclock and I decided to just
start from scratch for the most part. I pass 20+ hours of Small FFTs on
Prime95 and fail Blend test in about 11min with a rounding error. I
suspect memory. No temperatures have exceeded 44C on any core during
testing.

I have run Memtest and Windows Memory Analyzer program and revealed no
errors. I have run, MW:2 and WoW with no problems for a few days now
while I attempt to tweak settings. The only issue is the rounding error
in Prime95.

...and before you read the settings, yes I know my vcore is wicked low,
and increasing it has not yet yielded positive results. I am always open
to suggestions though.

Below are my data: Memset, CPU-Z, and BIOS settings...
(hardware is in my sig)

Code:
AI Tweaker
Ai Overclock Tuner: Manual
CPU Ratio Setting: 8.0
FSB Strap to North Bridge: Auto
FSB Frequency: 400
PCIE Frequency: 100
DRAM Frequency: DDR3-1601
DRAM Command Rate: 1N
DRAM CMD Skew on Channel A: Normal 
DRAM CMD Skew on Channel B: Normal
DRAM Timing Control: Manual

CAS# Latency: 7
RAS# to CAS# Latency: 7
RAS# to PRE Time: 7
RAS# ACT Time: 20
RAS# to RAS# Delay: Auto
REF Cycle Time: Auto
WRITE Recovery Time: Auto
READ to PRE Time: Auto

DRAM Static Read Control: Disabled
DRAM Dynamic Write Control: Disabled
Ai Clock Twister: Moderate
Ai Transaction Booster: Enabled Boost lvl: 1

Voltage Settings
CPU Voltage: 1.1875
CPU GTL Voltage Reference: Auto
CPU PLL Voltage: 1.5
FSB Termination Voltage: 1.10
DRAM Voltage: 1.90
NB Voltage: 1.25
NB GTL Voltage Reference: Auto
SB Voltage: 1.05
Clock Over-Charging Voltage: Auto

Load-Line Calibration: Enabled
CPU Spread Spectrum: Disabled
PCIE Spread Spectrum: Disabled

Advanced > CPU Configuration
CPU Ratio Setting: 8.0
C1E Support: Disabled
CPU TM Function: Enabled
Vanderpool Technology: Disabled
Execute Disable Bit: Enabled
Max CPUID Value Limit: Disabled

VID: 1.2375

I've tried a number of things including changing the Strap settings and
increasing the Vcore to 1.29, as well as raising the Vmch to roughly
1.31, disabling LLC. Vdroop is around .03 or so, nothing crazy.

3200GH-2.png
(opening the link in a new page will give better resolution)
 
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Some rams do not run at its specs very well. Try 787-20 and re-run Blend to see what happens. You could try to bump Dram voltage a notch like 1.92v
 
You should have just continued the thread you started in the Intel MB forum. I recommended settings for you to try when you were at 438MHz x 8, but you never responded to my specific settings suggestions. Only that you were able to bring down the vNB to 1.37V, and be Small FFT's stable in Prime for 8+ hrs. With a VID of 1.2375V, the Core Voltage as shown by CPU-Z needs to be at least equal to the VID while running Prime, so bump the Vcore to approx. 1.25 - 1.3V for the time being, and change these additional settings...

Code:
AI Tweaker
Ai Overclock Tuner: Manual
CPU Ratio Setting: 8.0
FSB Strap to North Bridge: 333
FSB Frequency: 400
PCIE Frequency: 100
DRAM Frequency: DDR3-1601
DRAM Command Rate: 2N
DRAM CMD Skew on Channel A: Normal 
DRAM CMD Skew on Channel B: Normal
DRAM Timing Control: Manual

CAS# Latency: 7
RAS# to CAS# Latency: 7
RAS# to PRE Time: 7
RAS# ACT Time: 20
RAS# to RAS# Delay: Auto
REF Cycle Time: Auto
WRITE Recovery Time: Auto
READ to PRE Time: Auto

DRAM Static Read Control: Disabled
DRAM Dynamic Write Control: Disabled
Ai Clock Twister: Auto
Ai Transaction Booster: Auto

Voltage Settings
CPU Voltage: 1.25 - 1.30
CPU GTL Voltage Reference: 0.63x
CPU PLL Voltage: 1.50
FSB Termination Voltage: 1.14
DRAM Voltage: 1.90
NB Voltage: 1.40 - 1.45
NB GTL Voltage Reference: 0.67x
SB Voltage: 1.05
Clock Over-Charging Voltage: Auto

Load-Line Calibration: Enabled
CPU Spread Spectrum: Disabled
PCIE Spread Spectrum: Disabled

Advanced > CPU Configuration
CPU Ratio Setting: 8.0
C1E Support: Disabled
CPU TM Function: Enabled
Vanderpool Technology: Disabled
Execute Disable Bit: Enabled
Max CPUID Value Limit: Disabled
 
Thanks Redduc, I bumped up the Vmch and VTT and ran for a few hours, then bumped the Vcore up to it's VID, the combination of the three seemed to have increased stability on the Blend test.
Was a pipe dream trying to get the Vcore to run at 1.20 :p
Temps looked good for the 3 hour run before errors at a max 46C

I'll do some more tweaking tonight and run it again and see if I can get a 24hr Blend stable config.
 
Switching to 2N doesn't seem to make a difference in stability. The ram is rated to run at 1N anyway. I have been running the blend tests lately and I will have two cores (same die it would seem) fail the test after about 2 hours, but the 2 on the other die will run for 12+ hours.

This is an obvious indication of a lack of Vcore, ya? So, I bumped it up to run at about 1.292 under load (LLC enabled,1.3065v in BIOS) but I get very random lock ups in which a grey or brown screen appears with vertical lines in it.

The only changes I have made above are;

VTT: 1.24
Vmch: 1.31 (anything above 1.39 causes me to fail post for some reason)

I dont have heat issues at all, I run no hotter than 44C under load on Prime and DIMMs are cool to the touch.

I have recently added a PCIe wireless network adapter to compensate for my current router situation. I haven't been able to find anything that this might affect. Also, I was having some issues with my mouse 'jumping' around. At the same time my network card would pick up a signal, but all web based activites would return, server not found.

So, I up'd the Southbridge Voltage which didnt seem to help on its own, but with a higher Vmch (1.35-1.37) the mouse and network adapter issue ceased.

However, I still get the odd screen lock ups mentioned above. Not sure where to start honestly.
 
Oh, I'd would also like to know where I can find information on where to start with assigning my own ram subtimings w/o letting the BIOS set it at Auto.
How does one know what all the subtimings should be set at?

I have no expertise to base this assumption on, but I feel as if alot of my stability issues I have had at higher FSBs have been RAM related.

In addition, my system really doesn't like running on any other Strap setting than Auto. 200 is unstable, 333 is moderately stable, and 400 is unstable.
 
Vcore: 1.24
Vmch: 1.31
VTT: 1.20
Strap: 333

1601 7-7-7-20-1N

intel burn test stable using 2900 of 3100 available memory for 20 passes, max temp 55C.

Oddly, fails Prime Blend on 1 core during the first iterations and the rest of the cores are good for 8+ hours.

What's the deal there?
 
Try setting both GTL Vref's to Auto, and bump the VTT from 1.2 / 1.24V to about 1.3V. Also change the Command Rate back to to 2N / 2T.
 
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