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Memory Compatability Question


westcoast_tech

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Hey everyone, first post

 

Im building a new system for myself and am wondering if I could get some advice on the RAM I should use

 

I am planning on using the ASUS P5Q Deluxe motherboard, have been looking at the TWIN2x4096-6400C4DHX

The QVL for the P5Q is strange, iv run across several of them, one of them does not mention this RAM and the other does

 

I would like to be able to eventually run 8 GB of memory, plan to start with 4 GB, so I would like to use 2 GB modules

 

I have read some threads of people having issues with this RAM, running both sticks or all 4, also issues running them at their designed specs

 

So my question, is this a good pair of sticks to be buying? I haven't used Corsair memory before but am very fond of their support, seems great!

 

I do not plan on overclocking much at all if any, reason why im planning on going with DDR2-800.

 

Also if this is RAM will work properly do I have to change anything in the BIOS or should I leave it at auto, id like to be able to run 4-4-4-12 timing, does that require the voltage to be set at 2.1v or is that only for overclocking, if I don't plan to OC should I leave the voltage at auto, or set it to 1.8v or what

 

Thanks

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Please research this thread:

 

http://www.houseofhelp.com/v3/showthread.php?t=64360&highlight=Unpredictable+results+QUAD2X4096+Gigabyte+X38-DS5

 

The issue is the On Motherboard (Intel) memory controller and a population of all four banks at the full speed of a two bank run. This issue is across the board with both Nvidia and Intel chipset based boards, DDR, DDR2 and DDR3.

 

Keep in mind that often issues arise in the longer term. The issues seldom damage the DRAM. They damage the on motherboard memory controller which has a harder time keeping up with the demands of a four DRAM slot population being run as fast as a two DRAM slot population. Those who want to be secure in their system either purchase a single kit of the DRAM capacity that the four singles have or they move to a higher bandwidth DRAM and drop the bandwidth. I also advise it as I have personally seen the issues that can and often do arise with a four DRAM slot population running at the full speed of a single kit speed.

 

I personally advise for a two stick solution as it is far gentler to the motherboard memory controller.

 

You will need to set the DRAM voltage to 2.1v to access the lower latencies of 4-4-4-12. This is not overclocking, it is setting to the spec of the DRAM.

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Thanks for the reply

 

So what I understand thus far is that if I plan on filling all 4 DIMMs I will have to lower the speed of whatever RAM im planning on running?

 

Such as if I purchase the TWIN2X4096-6400C4DHX I will most likely have to lower the speed from 800 MHz to 667 MHz with 4 DIMMs loaded

 

What if I were purchase the 2 x 2 GB Dominator DDR2-1066 RAM, would I be able to run that RAM with 4 DIMMs at 800 MHz?

 

Im not sure when/if I will ever need 8 GB of RAM however I like to leave as many options open as I can when possible

 

Thanks

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Thanks for the reply

 

So what I understand thus far is that if I plan on filling all 4 DIMMs I will have to lower the speed of whatever RAM im planning on running?

 

Such as if I purchase the TWIN2X4096-6400C4DHX I will most likely have to lower the speed from 800 MHz to 667 MHz with 4 DIMMs loaded

 

What if I were purchase the 2 x 2 GB Dominator DDR2-1066 RAM, would I be able to run that RAM with 4 DIMMs at 800 MHz?

 

Yes, it is advised to lower the DRAM speed if you populate with four DRAM slots. If you ran with 2 X 2048 of 1066Mhz DRAM, then you could run them at 1066Mhz. I have, on my main workstation (virtualization machine) 4 X 2048 of 1066Mhz CM2X4096-8500C5 (2 8500C5 kits) running at 1000Mhz with a 500Mhz FSB. So, with the overclock, this runs stable but I can't get stability any higher on the DRAM, even if I raise the FSB higher and the CPU tests at 528Mhz FSB with stability. So, there is an ability to overclock and gain a higher DRAM speed. However, there is no guarantee on the clock you can make.

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so if I did not plan to overclock would the dominator 1066 RAM be running at 800?

 

again about the XMS2 800, what should the voltage be to run that at 800 without OCing the FSB, 1.8v?

 

would I not possibly just be able to raise the voltage a little, say to 1.9v with the XMS2 if I had 4 DIMMs populated or would I have to lower

 

id like to be able to run 800 MHz

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so if I did not plan to overclock would the dominator 1066 RAM be running at 800?

 

again about the XMS2 800, what should the voltage be to run that at 800 without OCing the FSB, 1.8v?

 

would I not possibly just be able to raise the voltage a little, say to 1.9v with the XMS2 if I had 4 DIMMs populated or would I have to lower

 

id like to be able to run 800 MHz

 

You are advised to set the DRAM speed to 800Mhz, yes. The issue is not the DRAM when populating with four Dimms. The issue is the motherboard memory controller, so raising the Vdimm will not be beneficial although some have said they have found benefit from raising the Vdimm. Raising the MCH (Intel) / MCP (Nvidia) voltage will be of a greater benefit. Regarding the voltage. That DRAM has been tested to run with 1066 at 2.1v. You will have to find if you can make 800 with 1.8v.

 

Many people find issues when populating with four DRAM slots. Just read through this forum. Some find that even when setting to the proper values, lowering the DRAM speed, raising the MCH voltage, that they can still not find stability and must RMA the motherboard.

 

Go to any DRAM site and see that this issue abounds. You will find that motherboard manufacturers state maximum capacity and maximum speed, but NOT maximum capacity AT maximum speed and yes, there is a difference.

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If I am planning only to use 2 slots in total (seems better with less issues and 4 GB will prob be fine for myself for whatever I do), what modules would you recommend in that case as well if I do not plan to overclock the RAM

 

twin2x4096-8500c5df or twin2x4096-6400c4dhx?

 

again will be using

 

-P5Q Deluxe

-Intel e8500

-TT 850w

-ATI 4870 1 GB

Win XP Pro 32bit for now

 

thanks

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how about a stable 3.33 GHz? with the e8500

 

would you still recommend the C4?

 

what would be the BIOS values I would have to enter for the RAM if you don't mind my asking, it should be manually set correct?

 

thanks for the help, its greatly appreciated and confirms with myself I will choose to go with corsair RAM simply from the customer service, I have not yet experienced their quality but im sure I dont be disappointing

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A 400Mhz FSB will give you 800Mhz on the DRAM and is the route I would go. You would drop your multiplier to 8.5 and this would give you 3.4Ghz and a smooth 400 / 800 (CPU:DRAM) ratio which is inline with Intel Spec for the Q9770 and supported by the boards. In this way, you are overclocked, but still at Intel Spec. Intel FSB specs for Core 2 are 266, 333, and 400. Anything in between will work but is not in Spec. My advice:

Download memtest from--->

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

Download CPU-z from

Download Everest Trial Version from here -->

Enter your BIOS and set to these values:

AI Overclock Tweaker

Configure System Performance Settings

Ai Overclock Tuner = Manual
CPU Ratio Setting = 8.5
FSB Frequency = 400
PCI-E Frequency = 100
FSB Strap to Northbridge = 333
DRAM Frequency = Manual
DRAM CLK Skew on Channel A1 = Auto
DRAM CLK Skew on Channel A2 = Auto
DRAM CLK Skew on Channel B1 = Auto
DRAM CLK Skew on Channel B2 = Auto

DRAM Timing Control = Manual
DRAM Frequency = DDR2-800
DRAM Command Rate = 2N
DRAM Timing Control = Manual
CAS# Latency =  4
RAS# to CAS# Delay = 4
RAS# PRE Time = 4
RAS# ACT Time = 12
Row Refresh Cycle Time (tRFC) = 55 
All Else to Auto

DRAM Static Read Control = Enabled 
DRAM Read Training = Auto
Mem. OC Charger = Auto
AI Transaction Booster = Auto

CPU Voltage = Auto
CPU PLL Voltage = Auto
FSB Termination Voltage = Auto
DRAM Voltage = 2.1v
NB Voltage = Auto
SB Voltage = Auto
PCI-E SATA Voltage = Auto

Loadline Calibration = Auto
CPU Spread Spectrum = Disabled
PCIE Spread Spectrum = Disabled

Clock Over-Charging Voltage = Auto
Load Line Calibration = Auto
CPU GTL Voltage Reference = Auto
NB GTL Voltage Reference = Auto

Northbridge Chipset Config

Memory Remap - Enabled

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. Install Everest and right click on the (i) icon in the system tray. Choose Tools --> Cache and Memory Benchmark. Run the Benchmark and post the finished screenshot. Then we can move to a stability test.

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thanks man

 

I dont plan to even OC to that right away, ill stay at 3.13 GHz and if I feel I even need a little more i'll bring the FSB to 400 x 8.5

 

so since I dont plan to do that right away, to set the memory manually I suppose I would then leave the CPU stock at 333 x 9? and set the memory to DDR2-800, 4-4-4-12 at 2.1v?

 

in your configuration did you up the pci bus at all or is 100 standard?

 

I already have memtest+ 2.01 on cd, its a handy tool the new version is so much faster its great!

 

I have not heard of everest but when I get my system running ill go through the steps and post my results

 

thanks!

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thanks man

 

I dont plan to even OC to that right away, ill stay at 3.13 GHz and if I feel I even need a little more i'll bring the FSB to 400 x 8.5

 

so since I dont plan to do that right away, to set the memory manually I suppose I would then leave the CPU stock at 333 x 9? and set the memory to DDR2-800, 4-4-4-12 at 2.1v?

 

in your configuration did you up the pci bus at all or is 100 standard?

 

333 X 9 @ 800 4-4-4-12 2T with 2.1v. 100 @ PCI-e

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  • 2 weeks later...

Hey guys

 

So I was about to buy the XMS2 DDR2-800 2 x 2 GB RAM however the price just went up $50!

 

Im looking at the Dominator RAM and it's actually a few bucks cheaper at the moment for myself.

 

I'm thinking about going with the twin2x4096-8500c5df now because they are almost the same price, I suppose the performance difference is minimal however it seems like its the "better" RAM for cheaper.

 

Do you guys foresee any issues with that RAM and the P5Q Deluxe, I am aware it is listed on the QVL and from what iv been told in this thread it should be fine, just wanted to double check.

 

Would I be able to run that RAM at 800 MHz with 4-4-4-12 or does it require 5-5-5-12 no matter what the speed?

Also if I am not overclocking is there any reason for the fan or could I not bother with it, I do see the other kit without the fan but its a few bucks more lol

 

Thanks

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Do you guys foresee any issues with that RAM and the P5Q Deluxe, I am aware it is listed on the QVL and from what iv been told in this thread it should be fine, just wanted to double check.

 

No issues that I can see. I've had no problems with this marriage.

 

Would I be able to run that RAM at 800 MHz with 4-4-4-12 or does it require 5-5-5-12 no matter what the speed?

 

It's not a given, but I would say that you are very likely able to run 4-4-4-12 at 800Mhz.

 

Also if I am not overclocking is there any reason for the fan or could I not bother with it, I do see the other kit without the fan but its a few bucks more

 

I do not use the fan and I am overclocking. As long as you don't drive voltage > 2.1v through those modules I see no reason for the fan other than looks.

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