Max usable memory???

[jebuchanan]

I just upgraded my memory to Corsair 16GB (4x4GB) Vengeance DDR3-1600 Dual Channel.
My mobo supports 16GB, but it is saying only 8GB is available for use.
Does anyone know how to resolve this so I have all my memory available to use?
Thank you in advance.

 

[brianzion]

hi there

first please check how much ram is allocated

1 > windows key+R

2 > msconfig

3 > click ok

4 > click boot

5 > click advanced

6 > un-check maximum memory if ticked

 

[A Guy]

I think I found the answer, from you MB users manual:



Looks like DDR3-1600 are supported for one DIMM per channel only.

A Guy

 

[brianzion]

second check open resource monitor to see details of memory

1 > windows key+R

2 > type resmon

 

[brianzion]

here ia a good free program to see details of your ram called RAMMon by pasmark

link >>> PassMark RAMMon - Identify RAM type, speed & memory timings

RAMMon is an easy to use Windows based application that allows users to quickly retrieve the Serial Presence Detect (SPD) data from their RAM modules. It will allow users to identify a multitude of attributes, of which, includes the manufacturer, the clockspeed and other data of their DDR2, DDR3, XMP and EPP memory devices and even some older memory types. It uses SysInfo DLL SDK to gather the SPD attributes from RAM devices. This information provides a snapshot of the available data for each RAM module installed on the system.

What is SPD?
Serial Presence Detect (SPD) is the standard set forth by JEDEC for a host system to retrieve attributes of memory modules. The SPD standard is intended for use on any memory module, independent of memory technology or module form factor.

RAMMon displays the values stored on RAM module such as the memory capacity, the manufactuer, serial number, model part number, the CAS latencies supported and the module voltage.

Also, depending on your RAM type, other specific SPD data can be retreived as well. Such as the module thickness, module width, maximum operating temperature and more.

 

[brianzion]

I think I found the answer, from you MB users manual:

View attachment 152010

Looks like DDR3-1600 are supported for one DIMM per channel only.

A Guy

good call A Guy

 

[jebuchanan]

Explain 1 DIMM per channel?
I previously had DDR3-1600 4x2GB dual channel and had a total of 8GB memory.
Now I have DDR3-1600 4x4GB dual channel and have a total of 16GB, but only 8GB available.
Resmon and CPU-Z both say I have a total of 16GB installed.

 

[A Guy]

Hmmm, one dimm per channel on a dual channel MB, would mean a total of 2 dimms. This is for X.M.P. and DDR3 1600, according to the manual. But if you had 4 dimms of 1600 working ok before...

Let me do some looking. A Guy

 

[A Guy]

Find lots of people reporting similar problems, but few fixes. Have a look here:

Asus X58 + 6/12GB memory overclocking - detecting less memory than installed - i4memory.com - different look at memory

Most suggestions have to do with turning off the Auto settings in BIOS and setting the frequency and timings manually. Also suggestions to set the frequency at 1333 and seeing if that helps. What did the resource monitor report as far as ram installed? A Guy

 

[jebuchanan]

as I posted above, Resource Monitor says I have 16GB total RAM installed.

 

[marsmimar]

Could this possible have something to do with memory mapping?

The usable memory may be less than the installed memory on Windows 7-based computers

 

[jebuchanan]

I have seen this, but, no. BIOS is also reporting only 8GB available

This is the memory I was using.
As you can see, it is dual channel 1600. 2 kits giving me 8GB usable memory.

This is what I currently have installed.
This is also dual channel 1600.

This is the specs on my motherboard.

DDR3 dual channel architecture.

 

[marsmimar]

Please accept my apologies for these obvious suggestions. Have you tried swapping sticks to different slots? Running them one at a time to rule out bad memory? Do you have the latest BIOS from Asus? Have you tried lowering the memory frequency from 1600 to 1333 just to see if it makes any difference? I agree with A Guy's earlier post. I also found a lot of people reporting the same problem but no real solutions.

 

[jebuchanan]

BIOS 2401, latest version, swapping makes no difference, changing the frequency makes no difference, each DIMM checks out as good on its own. (tried this before you had asked)

 

[marsmimar]

I hate to leave a problem unsolved but I can't think of anything else you haven't already tried. Only other thing I can suggest is to contact Asus via Technical Inquiry Form or possibly their On Line Service (IM). This may be an issue with 7 not recognizing your available memory rather than a mobo or memory problem. Hopefully Asus has a solution. Or now that it's morning in Canada and the US some of our experts will be waking up with fresh eyes and ideas. Please post back if you find a fix so others can benefit from your aggravation.

ASUSTeK Computer Inc. -Support- Contact us

 

[jebuchanan]

I thank you for the response. I have already posted a request with ASUS, both their Tech support and via their Forums.

 

[marsmimar]

I thank you for the response. I have already posted a request with ASUS, both their Tech support and via their Forums.

Hopefully they'll have an easy fix and I'll slap my forehead for not thinking of it!

 

[sygnus21]

I thank you for the response. I have already posted a request with ASUS, both their Tech support and via their Forums.

OK, two things.....

Do the modules match?

Also have you checked to make sure the modules are running at their correct voltage?

Manually set the voltages for the modules. I suspect they may not be getting enough voltage, especially if you have the MB "Auto" set the memory. Do this manually and see what happens.

And yeah, according to the article a guy posted, you may have to drop your frequencies. Disable XMP (if enabled) and drop your frequencies to 1066MHz. You may be overloading your memory controller with all that RAM running at (trying to run at) 1600MHz.

That note is basically saying the memory controllers can't handle all that memory at those high speeds.

Let me know.

 

[jebuchanan]

All modules match, and voltages and timings are set correctly (all settings manually done, not Auto). XMP disabled, and dropping the frequency made no difference.
I am going to order 2 8GB kits of RipJaw 1333 memory as that should resolve the problem.
Thank you for your responses.

 

[sygnus21]

If the board is limited to a certain amount of memory at a certain speed, no matter what brand you put in, it's not going to overcome the limit placed by the MB manufacturer.

What you might want to do is see if there is a BIOS update that addresses/fixes the issue first.... instead of spending more money.

My two cents.