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Stuck with 4DIMMs?


Marakai

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Hello,

 

For a while now I've been suffering from repeated crashes of my system (Vista Ultimate 64-bit). I always blamed it on Vista, but after finally having had enough I thought I'd do some research and so have arrived here.

 

My mobo (GA-P35T-DQ6 rev 1.0) has 4 DIMMs of 2GB TW3X4G1333C9DHX (I think: the DIMMs actually say CM3X2048-1333C9DHX which I couldn't find in the drop-down list of the configurator) as I need 8GB for some of the work I do (lots of VMs).

 

I've followed all advice I could find here on changing voltage and what not. What I have *not* yet done is lower the 1333 speed to 1066. I'm reluctant to take the 25% hit as it's that extra speed I wanted in the first place!

 

Yet, from googling in general and here it seems that 4 DIMMs of DDR3 will generall not easily achieve full 1333 speed?

 

I've run memtest86+ I am getting a lot of errors. But at least it remained running.

 

Then for the heck of it I changed to 1066 - and memtest86 and the PC froze after merely 30 seconds, without having reported an error at all.

 

I'm really at a loss.

 

Has someone found the precise BIOS settings that would make my combination stable at full speed? Again, 1066 is not really acceptable and misses the point of why I would want 8GB of 1333 RAM in the first place. :(

 

Never mind that 1066 was *less* stable than 1333 - that could have been the wrong combination of parameters as it was a spur of the moment BIOS test.

 

Help!

Mike

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With 4 modules I would suggest setting the memory frequency at DDR1066 and set the memory Voltage to 1.7-1.90 Volts and set the NB/MCH/SPP Voltage to +.2 Volts as well and test the system with http://www.memtest.org. In addition, with some MB's (Mostly ASUS) you have to disable legacy USB in the bios when running any memory test.
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Thanks for that. I'd actually already done that last night (our night, I'm UTC+10).

 

I did various combination of +voltage on the DDR3 and on the NB MCH. Up to 0.3V.

 

With 1066 speed the system would actually be *less* stable, it would sometimes freeze just starting to boot of the memtest CD!

 

At least with 1333 the tests would run, but with errors.

 

Afterwards I did a separate memtest on individual sticks, single channel, one after another just to see if there's any obvious bad culprit. All tests ran fine. Oh, and just to see, I did those tests with all setting to auto (did a CMOS flush and started over with fail-safe BIOS settings and everything set to SPD).

 

Now, I'm upping it to 2 sticks, dual channel, and will test with mobo slots 1/3 and 2/4.

 

My suspicions are heading towards the motherboard, but I want to be sure. On the side, I've verified that my PSU should *not* be the problem either - it has all the ratings, is a good brand and with 750W should have power to spare!

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Well, I ran memtest86 for 11 1/2 hours with all 4 sticks.

 

Not one error.

 

Yet, when I booted Vista, the system froze within about a minute after logging in. I didn't get to do more than see if I could open Firefox.

 

I'm at a total loss, with so little diagnostics. :(

 

It's confusing and frustrating that despite the problems not starting until getting the 8GB, the memory gets an all clear, but the problems start up at once in Vista. And why only in Vista?

 

I now upped the NB MCH by 0.2V and am reinstalling Vista. We'll see.

 

Wish I had an old graphics card lying about to see if that might be the culprit.

 

Guess Corsair seems off the hook, sorry for the false alarm (?)

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I don't recall that setting, although maybe the Gigabyte advanced BIOS options (ctrl-f1) would have had them.

 

I can't check right now, as I ripped my mobo out and will replace it later today.

 

I'd first started suspecting the graphics card, but then found an ancient PCI card, and that didn't solve the problems either.

 

That mostly leaves the motherboard - or the PSU. It's a 750W Thermaltake Toughpower, you'd think that'd be just fine. Might swap it out, too, depending on what my local dealer has in stock.

 

Thanks for all your advice!

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Haven't done that - and not sure I would want to, unless to prove some problem in pre-SP1 Vista.

 

I reinstall the system pretty regularly for various reasons (I use it for work a lot - this is already costing me and the company money), and if I'd have to jump through those hoops every time, it'd be insane.

 

For now, I'll see if a new mobo solves the issue. It's already pretty self-evident that *something* is getting worse and dying as the issues are getting worse.

 

I used to be able to install just fine, the system would run and crash every few days. This has only now gone to the point where I can't even install.

 

All I need to know is what motherboard does Corsair recommend for the model of RAM I have. As I'd posted earlier, the DIMMs say CM3X2048-1333C9DHX (DDR3 1333 9-9-9-24 1.7V), which I can't find in the configurator dropdowns.

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Follow-up:

 

The replacement motherboard looks like it will be "tied" to an i7 CPU, not because I want to but because that's all the vendor has in stock and I need a system now to get back to work.

 

I'd like to re-use the RAM, but it's rated at 1.7V!

 

Which according to Intel Nehalem specs is a big Don't Do It! (anything above 1.65V can damage the CPU - OUCH!)

 

This is becoming some kind of comedy of errors! ;)

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Nehalem is a 1066Mhz FSB processor, so you can always give it a try. It will work in Dual Channel Mode and very likely if you set to 1.65v you will get 1333Mhz. It is tested and validated at 1333Mhz, but I think you will make 1333Mhz with 1.65v.

 

Follow-up:

 

The replacement motherboard looks like it will be "tied" to an i7 CPU, not because I want to but because that's all the vendor has in stock and I need a system now to get back to work.

 

I'd like to re-use the RAM, but it's rated at 1.7V!

 

Which according to Intel Nehalem specs is a big Don't Do It! (anything above 1.65V can damage the CPU - OUCH!)

 

This is becoming some kind of comedy of errors! ;)

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Hmm, interesting, except I never see this BSOD.

 

the system generally simply freezes at random points. Sometimes at an early installation point, sometimes I manage to boot, even get all the way to installing SP1 (and all patches!) and it still just freezes up.

 

The fact that these have gotten worse over time (from maybe once every so often to once a week to once a day to several times a day to now barely letting me install) does seem to point to some bitrotting hardware. ;)

 

It no longer seems to be the memory, so maybe I shouldn't even be spamming this forum. :D Bit I'll be buggered if I know what it is...

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Further Update:

 

I'm now typing this on a system with a new motherboard (Gigabyte EX58-UD3R) and an i7 920. All other components are the same.

 

I installed the machine with the minimum amount of RAM and patched it all the way up through SP1 and all critical and most recommended patches.

 

Interestingly enough the BIOS (says version F3) auto-detected my RAM as 1066 (8-8-8-20-2T), not 1333 (9-9-9-24-2T).

 

When I was done, I shut it all down and plugged in the rest of the RAM modules, leaving all BIOS settings as they were.

 

Again, the system froze pretty fast. :(

 

I've now set the default DRAM voltage of 1.5V to the highest "green" setting of 1.64V (1.66, the next highest is already "red"). I also changed the "performance" setting from Turbo to ... whatever it is, Normal, Standard.

 

So far, so good.

 

I won't do anything until this proves fairly stable, then gently see if I can get back up to 1333.

 

If anybody has advice on using my memory in this mobo, please post!

 

Cheers!

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Interestingly enough the BIOS (says version F3) auto-detected my RAM as 1066 (8-8-8-20-2T), not 1333 (9-9-9-24-2T).
This is because the memory is set to 1066 by the PNP BIOS that reads the JEDEC (Memory Standards) values of the SPD (Serial Presence Detect) programming.

 

I use XMP and set manually from there. I find this the most stable method of setting i7 up. But since you want to go fully manual, then:

 

These are the approximate settings I would use with your board, i7 920, 3 X 2GB of 1333C9. Also the testing I would perform on the memory.

Download Memtest86+ V2.11 from--->

and extract the ISO image. Burn the ISO image to an CD-ROM disk.

Download CPU-z from
.

Enter the BIOS and Enter these values:

Here is where I would suggest you start to run your ram with the above settings, and ram at 1333Mhz.

 

Advanced CPU Features

 

CPU Clock Ratio = 20x

Intel® Turbo Boost Tech = Enabled

CPU Cores Enabled = All

CPU Multi Threading = Enabled

CPU Enhanced Halt (C1E) = Enabled

C3/C6/C7 State Support = Enabled

CPU Thermal Monitor = Enabled

CPU EIST Function = Enabled

Virtualization Technology = Enabled

Bi-Directional PROCHOT = Enabled

 

Uncore & QPI Features

 

QPI Link Speed= x36

Uncore Frequency = 20 (Always 2x memory Multiplier or 2x +1)

Isonchronous Frequency = Enabled

 

Standard Clock Control

 

Base Clock (BCLK) Control = Enabled

BCLK Frequency (MHz) = 133

PCI Express Frequency (MHz) = 100

 

C.I.A.2 = Disabled

 

Advanced Clock Control

 

CPU Clock Drive = 800mV

PCI Express Clock Drive = 900mV

CPU Clock Skew = 0ps

IOH Clock Skew = 0ps

 

Advanced DRAM Features

Performance Enhance = Standard]

Extreme Memory Profile (X.M.P) = Disabled]

System Memory Multiplier (SPD) = 10.0 = 1333Mhz

DRAM Timing Selectable (SPD) = Manual

 

Channel A + B + C

 

Channel A Timing Settings

 

##Channel A Standard Timing Control##

CAS Latency Time= 9

tRCD = 9

tRP = 9

tRAS = 24

 

I will leave most of these on Auto for now, not the best for performance, but you can work on them after you get going

 

Channel A Advanced Timing Control

 

tRC = Auto

tRRD = Auto

tWTR = Auto

tWR = Auto

tWTP = Auto

tWL = Auto

tRFC = 82

tRTP = Auto

tFAW = Auto

Command Rate (CMD) = 2

 

Channel A Misc Timing Control

Round Trip Latency = Auto

 

Advanced Voltage Control

 

CPU

Load Line Calibration = Disabled

CPU Vcore = Auto

QPI/VTT Voltage 1.150v = ??? << This setting is tied to your CPU Memory Controller and its interconnect speed. Thus, this setting is dependent on your Memory multiplier used, QPI Speed, Uncore speed. Then tie this to what your CPU requires for stability. I suggest try setting to 1.2 - 1.3 and then either work your way down if it boots with 1.3, or up if not. You can also set to XMP and see the QPI/VTT voltage set to Auto and then set manually to the XMP value and work down from there.

 

CPU PLL 1.800v = Auto

 

MCH/ICH

PCIE 1.500v = 1.54

QPI PLL 1.100v = 1.1

IOH Core 1.100v = 1.14

ICH I/O 1.500v = 1.5

ICH Core 1.1v = 1.14

 

DRAM

DRAM Voltage 1.65v

DRAM Termination 0.750v [AUTO]

Ch-A Data VRef. 0.750v [AUTO]

Ch-B Data VRef. 0.750v [AUTO]

Ch-C Data VRef. 0.750v [AUTO]

Ch-A Address VRef. 0.750v [AUTO]

Ch-B Address VRef. 0.750v [AUTO]

Ch-C Address VRef. 0.750v [AUTO]

Run Memtest for two full passes. When assured of stable DRAM, then enter Windows and Run CPU-z and post screenshots of CPU-z's CPU, Memory and SPD tabs.

 

Results?

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Now *that's* what I'm looking for, many thanks! :D

 

OK, as a baseline here's the screenies of CPU-Z (I'd already run it first thing last night). I will still wait a few days, install and run more software, to see if things remain stable. Then, I'll come back and post results, maybe they'll be of use to others.

 

Do you think I should give XMP a try *before* I go manual?

 

Thanks again for your help! I haven't paid attention to this stuff in years, despite always building all my comps.

CPUZ-CPU.jpg.40fe205f52686a29934d0e8955f37ab1.jpg

CPUZ-Memory.jpg.91955027c9f33a82a2365604dfd0c614.jpg

CPUZ-SPD.jpg.839616fbc0e011ac37e3818a278385c7.jpg

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It's up to you, as it's kind of either/or. Now I personally integrate systems and as such, wish to create a fully stable system as quickly as I can.

 

My view?

 

XMP is the simplest method to set the memory. Then I can move to deal with the lowering of voltages, but if you want a stable system and no overclock, then manual settings are a waste of time unless it is necessary.

Now *that's* what I'm looking for, many thanks! :D

 

OK, as a baseline here's the screenies of CPU-Z (I'd already run it first thing last night). I will still wait a few days, install and run more software, to see if things remain stable. Then, I'll come back and post results, maybe they'll be of use to others.

 

Do you think I should give XMP a try *before* I go manual?

 

Thanks again for your help! I haven't paid attention to this stuff in years, despite always building all my comps.

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Update for those who care and/or may be in a similar situation:

 

It's been a whole weekend of heavy use and not one crash! <knocks on anything wooden in sight> :D All settings on the motherboard still at default/auto, except for DRAM voltage bumped to 1.64V.

 

On the side I've been playing catch-up to read up on the memory architecture for the i7 family.

 

Barring going through Intel's own docs, there seems to be remarkably little good technical info out there.

 

One thing I'm trying to understand is the triple channel architecture when using 4 DIMMs. The motherboard documentation and several web sources speak of "3+1", but I personally do not see how 3 goes into 4, so to speak. :)

 

One source (may have been the Wikipedia article, take that for what it's worth) also said the the mem controller switches to dual channel the moment you clock the RAM up to 1333MHz instead of 1066MHz. As a result you can end up with *slower* memory speed.

 

I might just have to break down and have a read of Intel's own docs. I'm not an EE, only a CS/IT geek, so this should be interesting. ;)

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The 3 + 1 is a hybrid mode being an amalgamation of triple channel and single channel and slower than triple channel. It is often called "Flex Mode". For optimal performance no more than three memory modules should be used. If four DIMMs are used, memory performance falls because the important memory parameter Command Rate can only handle two wait states. As well, you end up switching modes and the memory controller has to work much harder.

 

http://www.zdnet.com.au/reviews/hardware/desktops/soa/Benchmarks-Intel-Core-i7-Nehalem-/0,139023402,339293122,00.htm

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  • 1 month later...

Just for the sake of closure:

 

It's now been almost 2 months with my new Nehalem and a new motherboard. Using the same 8GB Corsair RAM that I used in my prior problematic system.

 

So far the system has been one of the most stable I have ever assembled!

 

I still run at 1066 with DRAM voltage set to 1.64V. It's smooth and speedy, I've not even felt the need to bump anything up or use XMP.

 

As it turned out, when I had a shop for a burn-in test on my old mobo, it turned out to be defect.

 

So, all's well as end's well! Thanks to all for the pointers and support!

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