# [SOLVED] How to add more RAM modules on a double channel motherboard?



## Vickyal (Feb 6, 2012)

The PC had only one RAM module of 2G DS when I purchased it







. 
I found 2 modules of the same brand and almost every specs as the OEM one. And was happy to add them onto the motherboard. But, something has been wrong. 
1. Every now and then, the PC shuts down by itself.
2. It stalls half way during the start of the PC.
3. It Beeeees sometimes when the power on button is pressed.
4. And a few crashes in the last few months.

I had the modules tested on other machines. They are normal when both of them are used for a week or two.

People say that the problem caused by the wrong order of inserting the modules into the slots.

How should the order be, please?

Thanks.


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## greenbrucelee (Apr 24, 2007)

*Re: How to add more RAM modules on a double channel motherboard?*

Well first let me say, when you were running just the one dimm (proper term for RAM module) you were not running dual channel you were running single channel.

The term dual channel means that you should be running 2 or 4 dimms or the same speed, same make, same voltage.

Now because you now have 3 dimms you are still running single channel and because your system is oem it may only really want one dimm or two dimms.

To run dual channel the dimms must be in the same coloured slots on the motherboard usually it's the slot closest to the cpu then the third slot. These are usually labeled as A1 and B1 (the others are A2 and B2).

Try with just two dimms.


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## Tyree (May 10, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

As above^
Using the 3rd stick is keeping you in Single Channel Mode and performance suffers. The problems you are experiencing could also be related to using RAM of different brands. 
RAM needs to be identical in brand/specs to avoid possible issues.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*

I cannot agree (though I don't yet disagree) with the above because we do not know your system specs and that is essential. 

SOME dual-channel motherboards are fully capable of running with 3 "sticks" and depending on how they are installed, the first two will run as a pair in dual channel mode, but the remaining one will run in single-channel mode. Or the first in single and the remaining two as a pair in dual channel. 

But again, that depends on your particular board/chipset so what it boils down to is RTFM - read the "fine" :whistling: manual. If you don't have your manual, you normally can download one from the motherboard or PC maker's website.

The manual will also tell you if you have to install the pair in adjacent slots or in the 1st and 3rd slots (or 2nd and 4th) . THERE IS NO INDUSTRY STANDARD for colors or labeling so unless you pulled that illustration out of the manual for your board, it may not be correct. 



> dimm (proper term for RAM module)


That depends on the module too. DIMM means "dual in-line memory module" and actually refers to how the memory devices (ICs) are configured or mounted to the PCB. So saying "memory module" is perfectly correct. And since this particular memory is "random access" memory, and these modules are used for random access, "RAM module" is also perfectly correct. But note there is also SIMM (single in-line memory module) as well as other memory module types. 

Personally, I like "sticks". Though not "proper terminology" by any means, it works without worrying which type you are using. 



greenbrucelee said:


> The term dual channel means that you should be running 2 or 4 dimms or the same speed, same make, same voltage.


Did you mean to say "at" the same speed...? If so, then I agree - assuming the sticks are inserted into the correct pair of slots.



Vickyal said:


> People say that the problem caused by the wrong order of inserting the modules into the slots.
> 
> How should the order be, please?


And they may be right. But to determine that with certainty, and also the correct order for best performance, we need to know the exact brand and model number of your motherboard. Without that, anything else is just a guess.


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## Tyree (May 10, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

Simple experiment. Install the two "new" modules into the proper slots and see if the PC starts/runs properly. :smile:


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

Gentlemen, 

Thank you very much for your kind instructions.

To me as a laywoman, all of your ideas are worthy very much for me to learn. But I feel a little bit hesitant to respond to any one of you because of the fact that I really do not know what to say.

To make it simple, I mean simple for me, please let me ask as the the questions as the following.

The OS installed is Win7 Pro. 64b.

1. 
Since I already have two more dimms which are the same brand and specs as the one originally installed by OEM, DS, 2G each, should I insert them into slot 1, 2 and 3? or 1, 3 and 4?

If 1 and 3 are a pair of the dual system, then the one in 2 runs as a single channel. Right?

It is said that 1 and 3 are a pair of the dual channel, and so also 1 and 4. If so, which two run in pair as dual channel and which one runs as a single if they are inserted into 1, 3 and 4 slots?


2. 
The motherboard supports upto 8GB
of RAM. And I have four same dimms, 2G and DS.
They have to be inserted 1, 2, 3 and 4 slots. Do they run as dual channel system or as single channel system?

Thanks.


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## Panther063 (Jul 13, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

If all Ram is identical and compatible with your system, then using four sticks of Ram will enable Dual Channel, using only three will result in all three running in single channel.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*



> ...using only three will result in all three running in single channel.


:sad: NO! That is not necessarily true! As I noted above, it depends entirely on the specific motherboard. Some boards WILL run in dual-mode with 2 sticks in the first channel and single-mode with 1 stick in the second channel. 

And also as I noted above, because there is no industry standard as to which pair of slots makes a channel; some boards use slots 1 and 2, while others use slots 1 and 3.

And with no industry standard for labeling or coloring, some may label the first channel as Channel A while others may be labeled Channel 0. And some may use different colors for the different channels and some may have all the slots the same color. 

@Vickyal - Until we know the exact brand and model number of your motherboard (or PC if factory built), then ANY suggestion you get as to which sticks go where is only a guess - and may be wrong! Though no harm will done if inserted in the wrong slots, you may not achieve optimal performance.

***

It is important to minimize handling of the memory modules. High density integrated circuits (ICs) like memory modules (and CPUs) are _extremely_ ESD (electrostatic discharge) sensitive devices. They can easily be destroyed by a static discharge from your fingers that is so tiny you (as a human) are unable to detect (hear, see, or feel) it. The result is MASSIVE lightning bolt digging a Grand Canyon sized, scorched, super highway (microscopically speaking) through 1000s of transistor gates in the IC!

Ensure you ALWAYS unplug the computer from the wall, and you touch bare metal of the case interior to discharge any static in your body BEFORE reaching into your case and BEFORE touching the RAM modules. And always hold the modules by the edges, not touching the electrical contacts. This will help minimize the potential for ESD damage. 

So it is important to KNOW exactly what you are doing before doing it. *Asking questions is great, but again, until we know which motherboard you have, EVERYBODY (including me) is just guessing!*


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## Tyree (May 10, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

From your diagram in Post #
The OEM RAM was installed in slots 1 & 3 so that would apparently be the Primary Channel.
Leave them as is and install the new RAM into Slots 2 & 4.
If all RAM is compatible, the PC should boot and run properly.



Vickyal said:


> I found 2 modules of the same brand and ALMOSTevery specs as the OEM one. And was happy to add them onto the motherboard. But, something has been wrong.
> 1. Every now and then, the PC shuts down by itself.
> 2. It stalls half way during the start of the PC.
> 3. It Beeeees sometimes when the power on button is pressed.
> 4. And a few crashes in the last few months.


The above would suggest the RAM is not compatible with either the Mobo or the OEM RAM. If the two "new" sticks will work properly, without the two OEM sticks and in Slots 1 & 3, that would indicate the new RAM is compatible with the Mobo but not the OEM RAM.
If you are using XP, 2GB of RAM is commonly sufficient. If your using a 32Bit OS, only about 3.25 of the 4GB can be accessed.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*

As I also noted above, IF that illustration in the opening post was pulled from the manual, then great! But it does not look like it came out of any motherboard manual - to me.


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## Panther063 (Jul 13, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*



Bill_Bright said:


> :sad: NO! That is not necessarily true! As I noted above, it depends entirely on the specific motherboard. Some boards WILL run in dual-mode with 2 sticks in the first channel and single-mode with 1 stick in the second channel.


I hate to argue a point but ....
Are you saying there are Motherboards that will run dual and single channel concurrently?
Because if you aren't, then MY post is correct and you have not proven it incorrect!
Populating three out of four Dimm slots results in single channel only.


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

Gentlemen, 

Thank you very much for your kind instructions.

To me as a laywoman, all of your ideas are worthy very much for me to learn. But I feel a little bit hesitant to respond to any one of you because of the fact that I really do not know what to say.

To make it simple, I mean simple for me, please let me ask as the the questions as the following.

The OS installed is Win7 Pro. 64b.

1. 
Since I already have two more dimms which are the same brand and specs as the one originally installed by OEM, DS, 2G each, should I insert them into slot 1, 2 and 3? or 1, 3 and 4?

If 1 and 3 are a pair of the dual system, then the one in 2 runs as a single channel. Right?

It is said that 1 and 3 are a pair of the dual channel, and so also 1 and 4. If so, which two run in pair as dual channel and which one runs as a single if they are inserted into 1, 3 and 4 slots?


2. 
The motherboard supports upto 8GB
of RAM. And I have four same dimms, 2G and DS.
They have to be inserted 1, 2, 3 and 4 slots. Do they run as dual channel system or as single channel system?

Thanks.

Aug. 17, 2014 adding the following:

Gentlemen,

Thank you again for your kind help!

The following information has been found from the original manufacturer, the Elitegroup:

The PC is manufactured by Acer. The motherboard G45T-AM2 V:1.0 in Acer's PC look identical asG45T-M2 V:1.0 manufactured by Elitegroup.

Could not find manual of this motherboard, but found one from Elitegroup.


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

This is a copy of the motherboard G45T-M2 made by Elitegroup.
It is G45T-AM2 when it becomes to be Acer motherboard.


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## Panther063 (Jul 13, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

I believe I have the Acer Motherboard in one of my computers and have the manual downloaded to my Laptop, I will look it up.
Edit, I have the 946GZT that looks similar


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

Thank you, Mr. Panther063!

It is very kind of you trying to help.
Really appreciate.

Thanks again.


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## Panther063 (Jul 13, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

"Under the north bridge, there are four 240-pin DIMM slots for DDR2 memory modules. They are partitioned into two groups with two slots in each. The first two slots refer to the first controller channel, with the other two to the second controller."
Excerpt taken from Digital-Daily: ECS G45T-M2 (Intel G45) | Motherboard Reviews
so installing one stick of Ram in the two slots nearest the CPU will enable dual channel, adding a stick of Ram to the third slot will make them run in single channel mode.


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

This is Vickyal again.
I have just read something just a few minutes ago, translated as the following:

If the motherboard is designed a dual channel board,
and if you want to take the advantage of the dual channel functionality,
and if there are 4 dimm slots on the board,
the 4 modules you want to insert into the 4 dimm slots MUST BE SS MODULES.

Gentlemen, your comments, please?

Thanks.


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## Panther063 (Jul 13, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

Sorry, I have never heard of SS modules.
But I do know all four sticks (or modules of Ram) must have the same specifications and either two or four sticks must be used.

I must also add, as you have not mentioned your Operating system and whether it is 32 or 64 bit, installing all 3 sticks will be pointless if your OS can not use it.


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## gcavan (Aug 13, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

*S*ingle *s*ided or Double-sided (DS) refers to the arrangement of the memory chips on just one side or on both sides of the module.



> If the motherboard is designed a dual channel board,
> and if you want to take the advantage of the dual channel functionality,
> and if there are 4 dimm slots on the board,
> the 4 modules you want to insert into the 4 dimm slots MUST BE SS MODULES.


May have been true with some boards. Most newer boards will accept either.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*



Panther063 said:


> Are you saying there are Motherboards that will run dual and single channel concurrently?


YES!!! That is exactly what I am saying! 

To repeat, again, there are some modern motherboards that WILL run 2 sticks in dual mode, and a third stick in single! And that is EXACTLY why I have been saying all along we need to stop guessing what Vickyal needs and research her specific board if we want our advice to be sound advice.



> Sorry, I have never heard of SS modules.


New kid on the block, huh? SS was around long (many years) before DS. So was DD (double density).


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## Panther063 (Jul 13, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*



Bill_Bright said:


> YES!!! That is exactly what I am saying!
> 
> To repeat, again, there are some modern motherboards that WILL run 2 sticks in dual mode, and a third stick in single! And that is EXACTLY why I have been saying all along we need to stop guessing what Vickyal needs and research her specific board if we want our advice to be sound advice.


This is obviously NOT a modern motherboard and *I don't* guess when offering advice.



Bill_Bright said:


> New kid on the block, huh? SS was around long (many years) before DS. So was DD (double density).


Hardly, and yes I have heard of single sided and double density ram, so there is no need to come in on your high horse trying to be a know it all! It was the phrasing of the question that threw me, if single sided was mentioned then it would have been an issue.


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## greenbrucelee (Apr 24, 2007)

*Re: How to add more RAM modules on a double channel motherboard?*

This isn't a modern board, its a pegatron and its also oem so it's possible that 3 dimms isn't compatible.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*



Panther063 said:


> This is obviously NOT a modern motherboard and *I don't guess* when offering advice.


Yeah, right! Because you knew the brand and model number before Vicky provided it.

High horse know it all? Yeah right. That's why I was asking for the model number and not giving advice without knowing what motherboard we were talking about. 

If you took offense to my comment about new kid on the block and SS modules, then I don't know what to say. With me being 62 and involved professionally with computer systems since the mid-70s, it sure was not meant in any offensive way, and it sure was not lashing out with puerile personal insults, as you did.  



greenbrucelee said:


> This isn't a modern board, its a pegatron


As Vickyal noted in post #13, it is an Elitegroup G45T-M2. It came out in late 2008 so while not state of the art new, it is not antique either. Plus the fact the owner's manual states on Page 1, "dual-channel _symmetric_ mode", it surely suggests they knew about asymmetrical dual-channel modes. 

I cannot find where this particular board is made by Pegatron but since Elitegroup and Pegatron have been conglomerate stable mates in the past, and both providing OEM boards to many makers, sure could be. 

Nevertheless, and sadly, the G45T-M2 manual does not clearly identify which pair is the first pair. I suspect careful examination of the board will reveal labels.

Interesting read: Intel Desktop Boards, Single and multi-channel memory modes


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## greenbrucelee (Apr 24, 2007)

*Re: How to add more RAM modules on a double channel motherboard?*

sorry I meant Elite group, still placement of dimms is usually 1 & 3 or 2 & 4 or all 4 not often 1,2 & 3 or 1,2 & 4.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*



> still placement of dimms is usually 1 & 3 or 2 & 4


I don't know about "usually" but certainly "often". You also "often" see 1 & 2 and 3 & 4 as well. As I noted, there is no labeling standard, or slot placement standard, for that matter - even within the same brand. I have two Gigabyte boards here that are labeled (starting from the CPU) as 4, 2, 3, 1 on one board and 2, 1, 4, 3 on the other. One with blue and white slots, the other with all black. 

You often see µATX boards with just two slots, 1 and 2. I can see where the maker of a sibling standard size ATX board with 4 slots would just add 3 and 4. 

There are dozens of motherboard makers and no set standards for labeling or colors or pairing. So we have to look them up. 


> not often 1,2 & 3 or 1,2 & 4.


I agree. I suspect that is usually on systems where the user had some extra RAM and plugged it in. But again, some boards can take advantage of that in Dual Channel, as shown in the Intel link above. 

I can't speak for triple channel boards as I don't have near as much experience with triple channel architecture. Dual channel, however has been around for 50 years, so that's a different story.


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

Gentlemen,

Thank you, all of you! Appreciate your help very much.

This is to share and learn.

To share:

1. Causing problems.
When the above mentioned 3 dimms were inserted in socket 1, 2 and 3, the arrangement caused serious problems:
1. Sounded BEEEEEE when power button was pressed.
2. Stalled half way during the start of the PC.
3. Shut down by itself.
4. Even crashed.

2. Running smoothly.
Now, the same dimms are inserted in socket 1, 2 and 4, the PC runs smoothly.

To learn:

According to the manual of the motherboard, the dual channels are devided as:
Channel 0 : DIMM 1 & DIMM 2
Channel 1 : DIMM 3 & DIMM 4

Therefore, installing dimms like this:
DIMM 1 and DIMM 2 = running thru channel 0.
DIMM 3 by itself = running thru channel 1.
should run as this: 
DIMM 1 and DIMM 3 = running dual channels thru 0 & 1.
DIMM 2 by itself = running single channel thru 0.
But this arrangement causes serious problems.
WHY??

And WHY an arrangement as the hereunder one runs smoothly?
Installing dimms like this:
DIMM 1 & DIMM 2 = running thru channel 0.
DIMM 4 a single = running thru channel 1.
and should run as this:
DIMM 1 and DIMM 4 = running dual channels thru 0 & 1.
DIMM 2 by itself = running single channel thru 0.
RUNS SMOOTHLY, WHY??

Is this motherboard capable of running dimms in odd numbers of dimms, meaning 3 modules?
Then one of the three modules is non-functioning even the PC can read its existence. 
The manual doesn't way anything, one way or the other.
Again, the myth is:
Dimms arranged in sockets: 1, 2 and 3 = PC crashes.
Dimms arranged in sockets: 1, 2 and 4 = runs smoothly.

WILL ANY ONE OF YOU GENTLEMEN SHARE YOUR POINT OF VIEW, PLEASE?

Thanks.


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## greenbrucelee (Apr 24, 2007)

*Re: How to add more RAM modules on a double channel motherboard?*

its most likely due to the OEM specifications.

On a normal motherboard lets say my motherboard for example if you have 2 dimms then the first dimm is in the first slot (closest to the cpu) then the third slot (these are the same colour whilst the other two slots are different colours).

It used to be that when ddr2 dimms came out that filling all four slots would cause voltage problems and sometimes you could get around that by changing the voltage to the memory controller sometimes noted in the BIOS as VCCSA.

With OEM boards the BIOS is usually locked so you cannot make adjustments. Usually on oem board you will find that parts of the board are not the same or not even there as opposed to the same board that is not OEM.

In my opinion if your board runs normally when the dimms are in 1,2 and 4 then there is no other configuration you can use.

It could also be that your board can only run smoothly with a certain speed or make or RAM. There should be a qvl list for your board in the manual or on the boards site.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*



Vickal said:


> But this arrangement causes serious problems.
> WHY??
> 
> And WHY an arrangement as the hereunder one runs smoothly?
> ...


@Vickyal - First, I apologize for the distraction and thanks for sticking with us. And for sure, do not feel for a second that any of the responders in this thread are purposely trying to lead you astray. That could not be further from the truth. 

As to your questions about your computer, at this point, it is anyone's guess. If I had this computer in my shop and on my bench right now, I would swap out your power supply for a known good supply. That's because I want to know for a fact I am supplying the system, good, clean and stable power. Then I would pull your 3 sticks and install 4 identical and compatible, known good sticks to see what happens.

One or more of your sticks may be just a little out of dead-center specs in one direction (but still within tolerances) and another stick, or the controller may be just a little out in the other direction. "Additive tolerance variations" can result in the combined gaps being just a tad too far to remain stable. *That's a guess*, but it happens - though less so with DDR3 and current boards. 

RAM can pass every test out there, but then refuse to "play well" when installed with other sticks. That happens too, but again, less so with DDR3 and current boards. 

Still, it might be a good idea to test your RAM. Here's my canned text on that: You can test RAM using one of the following programs. Both require you to create and boot to a bootable floppy disk or CD to run the diagnostics. Allow the diagnostics to run for several passes or even overnight. You should have *no* reported errors.

*Windows Memory Diagnostic* - see the easy to follow instructions under _Quick Start Information_,
or
*MemTest86+* (for more advanced users) - an excellent how-to guide is available *here*, 
or
Windows 7 and Windows 8 users can use the built in *Windows Memory Diagnostics Tool*.​
If you get an error, you might try pulling two sticks and run the tester again, swapping sticks as necessary to determine which one is causing the error. If you get even just 1 error, that stick is bad - without a doubt. But again, these testers are not conclusive. The RAM can pass but still fail when put in circuit. 

***************



greenbrucelee said:


> On a normal motherboard lets say my motherboard for example if you have 2 dimms then the first dimm is in the first slot (closest to the cpu) then the third slot (these are the same colour whilst the other two slots are different colours).


:frown: I am sorry, but you are still stuck on a FALSE BELIEF and that really needs to change! At least it needs to change if being correct and giving good advice is the intent. Otherwise, it is providing wrong information! And I don't believe for a second that is the intent, or the intent of any of the other responders here on this site. 

THERE IS NO "_NORMAL_" MOTHERBOARD!!!!! What we see on our motherboards does NOT, in ANY WAY, suggest that is how it is on other boards, or that our board is "normal" - other than what the ATX Form Factor Standard requires, which does NOT include RAM slot labeling, color coding, or first pair physical location!!!

*Don't believe me?* Then see for yourself. Look at the illustration below for the popular Gigabyte GA-P55 series board, the first pair (1 and 3) are NOT "_closest to the CPU_!" Neither are they on the GA-Z77-D3H (see page 7) where you can see the slots are labeled (starting from the CPU) 4, 2, 3 and 1, all 4 slots are black and the first "pair" is 1 and 2, not 1 and 3! And again, NOT "_closest to the CPU_!" 

ASUS Z97-PRO(Wi-Fi ac), Page 1-4 - NOT the 1st and 3rd! And if you look in section 1.2.4 for instructions to install the first pair, you insert them in slots A2 and B2!!! The 2nd and 4th slots - and once again, NOT "_closest to the CPU_!" 

*Three different boards, 2 makers, all different, and not one the same as your board! * So how is yours "normal"?

PLEASE!!! For our own integrity, the integrity of this site, and, most importantly for the folks we are helping, stop assuming what we "think" is normal or standard, is normal or standard. Even if it "was" normal "today", there is nothing to suggest it will be normal tomorrow. Why? Because, once again :banghead:, there are no industry standards!!!! At least not for RAM slot labeling, color coding, or first pair physical locations. 

*BUT DON'T TAKE MY WORD FOR IT!!! SEE (and VERIFY) FOR YOURSELF!!!! * And please understand, I know how to use Windows, but I don't pretend to be a Windows expert. In fact, I am not an expert on the inner workings of ANY software! 

But I know electronics. I know how electrons flow through devices and circuits. And specifically, I know my way around computer hardware and I know how the primary function of an operating system facilitates I/O communications between hardware devices. You can follow the link in my sig and decide for yourself if I might have a clue about what I am talking about. 

Computer hardware support is NOT just a hobby for me. It is how I have supported my family for 40+ years! 

*****


> It used to be that when ddr2 dimms came out that filling all four slots would cause voltage problems


NO!!! Got a link showing this was a widespread, "inherent" problem with all, most, or just many 4 slot boards? 

I am sure you can find some forum posts reporting individual cases where this is true, but how about articles or white papers published by ANY reputable hardware review site, RAM maker, Intel or AMD, or a motherboard maker that reports this is a systemic problem?

That was seen on a very few (relatively speaking) "new generation" DDR2 boards and often involved incompatible RAM. Similar things happened when DDR3 first came out. And in each case, it was soon corrected with BIOS updates - and enhanced publications of RAM QVLs to help ensure users updated with compatible RAM. The TRUE fact is that the vast majority of 4 slot DDR2 boards had (and have) no problems whatsoever from day 1 when fully populated. 



> With OEM boards the BIOS is usually locked so you cannot make adjustments.


:frown: Again, not true - at least not as a rule or for the majority of OEM boards. Yes, you may not be able to get rid of the Dell logo, or you may not be able to use an HP install disk on the Dell system, but you can still make MANY adjustments on the vast majority of OEM boards - including overclocking adjustments. 

Certain, very low-budget, entry-level eMachines, or no-name generic PCs are likely to be more restricted because these cheap systems provide no room for upgrades. But the BIOSs are still not locked. Even notebooks, which are very proprietary do not have locked BIOS. If locked, a user could not update (flash) the BIOS if a new version was released. 



> In my opinion if your board runs normally when the dimms are in 1,2 and 4 then there is no other configuration you can use.
> 
> It could also be that your board can only run smoothly with a certain speed or make or RAM. There should be a qvl list for your board in the manual or on the boards site.


:smile: Now except for upgrading with a new "pair" of sticks for 4 total, I agree with this completely. And for sure, for anyone building a new computer, or upgrading RAM on an old, it is important to check the Qualified Vendors List (QVL) for RAM compatibility. There are just too many RAM makers and RAM models for motherboard makers to test them all, so you don't have to buy listed RAM. But you do need to buy RAM with the same specs as listed RAM. For CPUs, you need to buy a CPU listed on the CPU QVL.


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## greenbrucelee (Apr 24, 2007)

*Re: How to add more RAM modules on a double channel motherboard?*

The last two asus board I have had said it must be 1 & 3 if using two dimms.

In my experience it did cause voltage issues I personally had 4 boards that I worked on to fix that issue.

Show me a current DELL or HP system that you can fully make adjustments to in the BIOS, and I'm not talking about Alienware.


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*



> Show me a current DELL or HP system that you can fully make adjustments to in the BIOS,


Now you are changing your tune in the middle of the stream. 

_"Fully make adjustments"_ is NOT anywhere near the same thing as what you said earlier when you said,


> With OEM boards the BIOS is usually locked so you cannot make adjustments.


That says, or at least implies "all" or at least "most" OEM boards are (1) "locked" and (2) you cannot make changes. Both are just not true! 

And I am not talking about simple things like data and time or boot order, but other changes that users might want like various Wake on... commands, power management, security settings, integrated peripherals, PC Health, case intrusions and more. 

You are also implying that users of OEM boards cannot overclock their systems! Totally false (except maybe very budget, entry level systems) as that definitely requires advanced settings changes. You don't need an Alienware system to overclock a Dell. Or do you deny that too? 

If the BIOS was locked as you suggest, users may not be able to upgrade the CPU, change 1st monitor settings, change how their power button works and more.



> The last two asus board I have had said it must be 1 & 3 if using two dimms.


:facepalm: So your "two" boards, out of 100s of board makers and 1000s of boards establishes the "norm"??? :banghead: 

I just provided you proof of a current ASUS board where the 2nd and 4th slots are used if using two dimms. And I just provided you proof of two Gigabyte boards too. Did you look at those links to see that I am not blowing smoke up your a$$? :nonono:

I don't provide links for my benefit. It is so you DON'T have to believe me, but can see for yourself. So DON'T BELIEVE ME! See from the horse's mouth yourself!!!!

Okay, here is the "official" ATX Form Factor Standard. This is the guiding directive all PC motherboard maker's MUST comply with if they want their boards to be ATX Form Factor compliant so it WILL work with ATX cases and ATX power supplies. Please show us in the official ATX Form Factor standard where; 
(1) slots must be color coded, 
(2) must use 1 and 3 for the first pair, 
(3) the first slot for the first pair is closest to the CPU, and 
(4) must be labeled in a designated way.​


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

Have found Acer's motherboard on M5700.
It is different in some aspects.
Acer's G45T-AM2 motherboard says:
"Dual-channel support on four dimms."
Does this mean that there must be 4 modules inserted into 4 slots in order to have the dual channel functionality work?


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## Bill_Bright (Dec 17, 2004)

*Re: How to add more RAM modules on a double channel motherboard?*

That information does not tell us one way or another. And sadly, the text of your manual is not that clear either. However, to take "full" advantage, you would want to fully populate with 2 pairs of DIMMs. 

That said, understand no "harm" is done if you run in single mode. And depending on all sorts of other factors, in many cases, more RAM in single-channel mode may offer better performance than less RAM in dual-channel mode. 

If the CPU and OS do not have enough "room" to operate in without constantly spooling data out to the Page File on the slow (compared to RAM) hard drive, then it makes no difference how fast the RAM is working at! 

So I say, try it and see what happens - until the budget allows you to fill all slots.


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## Tyree (May 10, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*



Vickyal said:


> Does this mean that there must be 4 modules inserted into 4 slots in order to have the dual channel functionality work?


No. You need to have two or four sticks installed, of matching brand/specs and in the appropriate slots, for Dual Channel Mode.


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## greenbrucelee (Apr 24, 2007)

*Re: How to add more RAM modules on a double channel motherboard?*



Tyree said:


> No. You need to have two or four sticks installed, of matching brand/specs and in the appropriate slots, for Dual Channel Mode.


This is what I said however many posts ago bit it was dismissed.


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## Vickyal (Feb 6, 2012)

*Re: How to add more RAM modules on a double channel motherboard?*

THANK YOU, GENTLEMEN!

MY PROBLEM ON THE MOTHERBOARD IS STILL THERE.
BUT I CONSIDER MY QUESTION IS WELL ANSWERED.
THIS CONCLUDES THIS POST WITH APPRECIATIONS AND THANKS.

AGAIN, THANK YOU, GENTLEMEN!


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## Tyree (May 10, 2009)

*Re: How to add more RAM modules on a double channel motherboard?*

You're welcome. Your problem will most likely continue while attempting to use mismatched RAM that may not be compatible with one another and/or the Mobo.


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