ASRock G31M-S R2.0: problems handling 8GB RAM as specified

[Vince_]

Hi all,


First of all, here are the specs of my config:
ASRock G31M-S R2.0
BIOS 2.10
Intel Core 2 Quad Q9650
4GB RAM (2x2GB) PC2-6400
750 Watts PSU
NVIDIA GeForce GTX 480
SATA 120GB SSD disk #1
SATA 2TB disk #2
IDE DVD-RW
Windows 7 Pro 64 bits


I was very happy with my config until I decided to upgrade the RAM from 4GB (2x2GB) to 8GB (2x4GB).


This mobo supports 8GB maximum as specified on ASRock website:
ASRock > G31M-S R2.0


Within this document from the ASRock website, several references of DDR2 4GB modules compatible with ASRock G31M-S R2.0 mobo are listed:

http://www.asrock.com/mb/memory/G31M-S%20R2.0.pdf

As everybody knows, it is very difficult to find 4GB DDR2 modules, especially if you are hunting against a specific reference, but I was enough lucky to find and buy two modules totally new (sealed boxes) officially supported by my mobo:
(label on the boxes)
Kingston KVR800D2N6/4G
4GB PC2-6400 CL6 240-Pin DIMM


Yes, you guessed right, it does not work...


Symptoms:
- boot with 1x4GB (module 4GB #1): does not work at all! (no beep, no POST, nothing...)
- boot with 1x4GB (module 4GB #2): does not work at all! (no beep, no POST, nothing...)
- boot with 2x4GB (both 4GB modules): does not work at all! (no beep, no POST, nothing...)
- boot with 1x2GB+1x4GB (module #1 or #2, same behaviour): 2048MB at POST display, and when I enter BIOS: 2GB module is recognized as 2048MB and 4GB module is recognized as 2MB!!!


When I start PC with 2GB+4GB modules:
- Windows 7 Pro 64 bits system recognizes only 2GB amount of RAM (4GB module is not used),
- CPU-Z (last version 1.73.0.x64) finds both 2GB and 4GB RAM modules (logs ok, see txt file),
- memtest86+ (last version 5.0.1) finds both 2GB and 4GB RAM modules (all the tests run ok).


It seems to me the two 4GB modules are ok, but the BIOS cannot handle them properly.
Is there any beta BIOS handling 4GB modules as specified by official specs of the mobo?
Does anybody have any idea about what I missed?


Thanks,


Vince

[SandsOfTime]

Re: ASRock G31M-S R2.0: problems handling 8GB RAM as specified

Did you made a cmos reset after installing the 4GB modules?

[Vince_]

Re: ASRock G31M-S R2.0: problems handling 8GB RAM as specified

Did you made a cmos reset after installing the 4GB modules?

Yes, I cleared CMOS, then set RAM voltage manually to 1.8V and finally increased the NB voltage... nothing happened.

[SandsOfTime]

Re: ASRock G31M-S R2.0: problems handling 8GB RAM as specified

Hmm, this reminds me of a GSkill 2x2GB kit I had some years ago. One year later I bought another kit with exactly the same name, but they didn't work together and were recognized by the bios sometimes yes, somtimes no. Finally I found out the reason: the older kit had internally 1 rank and the newer kit had 2 ranks.

Maybe this is the same problem with your kit. Although it has the same name that is on the compatibility list for your motherboard, it could have another internal configuration that makes it incompatible with your motherboard.

[Vince_]

Re: ASRock G31M-S R2.0: problems handling 8GB RAM as specified

Hmm, this reminds me of a GSkill 2x2GB kit I had some years ago. One year later I bought another kit with exactly the same name, but they didn't work together and were recognized by the bios sometimes yes, somtimes no. Finally I found out the reason: the older kit had internally 1 rank and the newer kit had 2 ranks.

Maybe this is the same problem with your kit. Although it has the same name that is on the compatibility list for your motherboard, it could have another internal configuration that makes it incompatible with your motherboard.

If it is the case, I cannot do anything!

[ASRock TSD-Eddy]

Re: ASRock G31M-S R2.0: problems handling 8GB RAM as specified

Dear Vince_

Due to Intel of G31 chipset limitation, G31M-S R2.0 support single-sided memory DIMM up to 2GB(256MB per chip).
ASRock > G31M-S R2.0
Please check whether your 4GB memory is doubled-sided or single-sided with memory vendor.

http://www.asrock.com/mb/images/RAMDoubleSide.png

In order to maximize the system memory, please install 4GB memory module with 16 cells or 2GB memory modules with at least 8 cells.
4GB with 16 cells:http://www.asrock.com/mb/images/RAMDoubleSide.png
2GB with 8 cells:http://www.asrock.com/mb/images/RAMSingleSide.png

Best wishes
ASRockTSD
Eddy

[profJim]

Re: ASRock G31M-S R2.0: problems handling 8GB RAM as specified

Dear Vince_

Due to Intel of G31 chipset limitation, G31M-S R2.0 support single-sided memory DIMM up to 2GB(256MB per chip).
ASRock > G31M-S R2.0
Please check whether your 4GB memory is doubled-sided or single-sided with memory vendor.

http://www.asrock.com/mb/images/RAMDoubleSide.png

In order to maximize the system memory, please install 4GB memory module with 16 cells or 2GB memory modules with at least 8 cells.
4GB with 16 cells:http://www.asrock.com/mb/images/RAMDoubleSide.png
2GB with 8 cells:http://www.asrock.com/mb/images/RAMSingleSide.png

Best wishes
ASRockTSD
Eddy

http://www.kingston.com/dataSheets/KVR800D2N6_4G.pdf

[Vince_]

Re: ASRock G31M-S R2.0: problems handling 8GB RAM as specified

Hi Eddy,

Dear Vince_
Due to Intel of G31 chipset limitation, G31M-S R2.0 support single-sided memory DIMM up to 2GB(256MB per chip).
ASRock > G31M-S R2.0
Please check whether your 4GB memory is doubled-sided or single-sided with memory vendor.

Would you mean the official ASRock documentation (http://www.asrock.com/mb/memory/G31M-S%20R2.0.pdf) is wrong about 8GB max RAM possible and the various 4GB modules supported?
The memory modules I bought are definitively double-sided 4GB modules, bought because listed in ASRock'QVL.