Is there any Corsair RAM that will work at 4GB in an Asus P5B-deluxe?

[Knobbicus]

I've been getting the runaround from both Asus and Corsair regarding this question:

 

Asus says "Get the correct timings (etc) from Corsair for this to work."

 

Corsair says "This is a limitation of the chipset."

 

Perhaps I've been asking the wrong question. I already have 4GB of Twin2x2048-6400C4, and the BIOS (note, i said BIOS, not OS) reports 3584 MB ram, as opposed to 4096. I'll also mention that with 3 sticks installed, it reports 3072, with 2 sticks installed it reports 2048. And I've been trying to get these particular sticks to work.

 

The new question is:

 

Can Corsair recommend any Corsair RAM to put in this system and see 4GB? I'm hoping, given the number of posts I see regarding the P5B, that somewhere Corsair actually has a P5B and can just test it. I'd be very interested to hear what is observed.

 

So, to recap: Is there any Corsair ram that I can put in this mobo and see the full 4096 mb? I asked a simiar question as a case number, but the reply was something like: "The AGP aperture and other system processes are reserving some RAM, so you won't be able to see it. And besides, 32-bit OSes won't address >~3gb ram." (That's why I said BIOS.) But there was no explanation about why the AGP and other processes would cause the BIOS to under-report the ram at 4GB and not at 3GB or 2GB.

 

Ok, rant over. Still looking for suggestions.

 

-knobbicus

 

p.s. Here- I'll just post the reply from the case number, and you guys can read it for youselves:

 

This is a chipset and O.S. limitation. The MB will see a max of 4 Giga Byte 4000 M-Byte not 4096 M-Byte of memory and the memory used for cache will come off the top like for cache on your CPU and memory in your Video card. In addition, what ever you have the AGP aperture size set too will also come off of that number as well.

Example:

4 Giga Bytes = 32,768 M-Bits

Any 32 Bit O.S. or Chipset will only see 32,000 M-Bits

Then it would have to subtract any other memory used in the system like for your Video card and or cache on your CPU, LAN or Modem, and the MB bios may reserve some for caching as well. That would the total size of memory accessible to your system, something between 2.6 to 3.2 Gigs of available memory.

 

So, since there is no OS installed yet, let's consider the chipset. If it can only address 32 bits, meaning 32,000 M-bits, then I'm limited to memory sizes somewhere below that number. So, a little math is applied, and I find that if I lose the ability to address 128MB of ram, I now should see 3968 MB, which comes out to 31744 Megabits. Below the 32,000 cap. Fine, I say. So why do I see a loss of 512MB? Furthermore, to extend this logic, the mobo/chipset should see a max of 2,000 MB at 2GB and 3000 MB at 3GB install, and I won't see it report 2048 or 3072. So why is it that I see the BIOS report exactly these values? This explanation seems incorrect.

 

Ok, I need to go and do something productive. Anyone have any thoughts or comments?

[RAM GUY]

First thing,

You are using information thats published for another chipset Intel I875 which is a 32 Bit chipset? And that information would apply to that chipset or any 32 Bit chipset. So What is the chipset that you have and what are its limitations? ASUS P5B Spec.

4 x DIMM, max. 8GB, DDR2 800 / 667 / 533 MHz, non-ECC, un-buffered memory

Dual channel memory architecture

* Refer to http://www.asus.com or user manual for Memory QVL (Qualify Vendor List)

And in your bios there should be a setting to remap the memory if you are using a 64 Bit OS and that may or may not change the total size of memory shown in the bios and or Windows. Also with Intel platform MB you would need to have a CPU that supports 64 Bit extensions in order to see more than 4 Gig of memory. Check with Intel about the specific core of CPU that you have!

 

However, if you are using a 32 Bit O.S. all will be a mute point and you will never see the full 4096 Meg of memory in Windows. And what you have reported the bios reports 3584 MB ram may verry well be correct for this MB as it may be reserving some memory for PCI caching, you would need to ask ASUS about that!

[Knobbicus]

Hi Ram Guy-

 

Thanks for the reply, I will attempt to address your questions one at a time.

 

 

First thing,

You are using information thats published for another chipset Intel I875 which is a 32 Bit chipset? And that information would apply to that chipset or any 32 Bit chipset. So What is the chipset that you have and what are its limitations? ASUS P5B Spec.

 

Quote:

4 x DIMM, max. 8GB, DDR2 800 / 667 / 533 MHz, non-ECC, un-buffered memory

Dual channel memory architecture

* Refer to http://www.asus.com or user manual for Memory QVL (Qualify Vendor List)

 

[end quote]

 

My chipset is the Intel P965 Express chipset. I can't find any literature at Intel describing whether it is a "32-bit chipset" or not, but it is able to address up to 8GB of RAM (http://www.intel.com/design/chipsets/express_flyer.htm). From the Asus manual for the P5B-deluxe wifi (my board), the Quality Vendor List shows (among others) the following information in the DDR2-800 compatibility list:

"1024MB CORSAIR CM2X1024-6400C4"

 

(The corsair website describes my TWIN2X2048-6400C4 as being "Two matched CM2X1024-6400C4 modules".)

 

This is on page 2-15 of the P5B manual, Second Edition V2 from July, 2006. The manual online at the Asus website is version 1 fromm June, 2006, fyi.

 

And in your bios there should be a setting to remap the memory if you are using a 64 Bit OS and that may or may not change the total size of memory shown in the bios and or Windows. Also with Intel platform MB you would need to have a CPU that supports 64 Bit extensions in order to see more than 4 Gig of memory. Check with Intel about the specific core of CPU that you have!

[end quote]

 

I have the setting to remap the memory enabled (the actual line item is called "Memory Remap Feature"). This increases the detected RAM from 3072 to 3584 when I have 4 sticks of 1GB installed. I am running Windows XP x64, and windows reports 3668924 kB physical memory installed, which is equal to 3582.9 MB physical RAM. Which is essentially identical to the 3584MB RAM reported by the BIOS.

 

I am using the E6400 Core 2 Duo CPU, so no troubles there. It's a 64-bit CPU.

 

However, if you are using a 32 Bit O.S. all will be a mute point and you will never see the full 4096 Meg of memory in Windows. And what you have reported the bios reports 3584 MB ram may verry well be correct for this MB as it may be reserving some memory for PCI caching, you would need to ask ASUS about that!

[end quote]

 

Well, as I said before, I have asked Asus about that, and Asus says that their mobo/BIOS/chipset combo will report 4096MB if 4096MB is installed, and they say it's a function of the RAM. They say there is no additional RAM reserved for caching as reported in the BIOS- it reports what is installed. Furthermore, I've checked this by removing 2 sticks of ram. With only 2GB installed, the reported RAM is 2048MB, with no other settings changed. If PCI caching or AGP aperture were consuming RAM, it should still be consumed with only 2GB installed, yet the full 2048 is being reported under these conditions.

 

Any other ideas?

 

Thanks very much,

Knobbicus

 

p.s. Sorry for the odd quoting system, I don't know how to use the multiquote feature yet.

[RAM GUY]

Can you tell me the CPU SKU NUmber and what Bios version do you have installed?

[Knobbicus]

Absolutely:

 

BIOS is rev 0804, released Oct 30, 2006 (but created Oct 20, 2006 according to the BIOS readback), this is the most recent BIOS for this board.

 

I'm not positive which number on the Intel box is the SKU, there are a lot of numbers! But I think it is the Product Code: BX80557E6400SL9S9

 

Here is the spec sheet from Intel regarding this CPU:

http://processorfinder.intel.com/details.aspx?sspec=sl9s9

 

 

Let me know if there is any more info I can provide.

 

Thanks,

knobbicus

[RAM GUY]

All I can tell you is it should be working and you should see 4096 of memory in your Bios setup with the remap setting enabled; the CPU you have supports it and so should the Bios and the fact that both sets report properly 2048 Meg of memory would suggest its MB/Bios issue. Have you talked to ASUS? Also what Video card did you have installed? Have you tried a different Video card to see if that might be causing the problem?

 

I would try and re-flash your bios to the latest version even thou its the same just re-flash it using the dos based flash utility then clear the bios with the power and battery removed and when you go to Bios setup load setup defaults and set the proper settings for Voltage and timings DDR667 at 2.1 Volts and enable the remap setting and then let it boot to a boot disk from http://www.memtest.org and see if it see's the correct size of ram.

[Knobbicus]

All I can tell you is it should be working and you should see 4096 of memory in your Bios setup with the remap setting enabled; the CPU you have supports it and so should the Bios and the fact that both sets report properly 2048 Meg of memory would suggest its MB/Bios issue. Have you talked to ASUS? Also what Video card did you have installed? Have you tried a different Video card to see if that might be causing the problem?

 

I would try and re-flash your bios to the latest version even thou its the same just re-flash it using the dos based flash utility then clear the bios with the power and battery removed and when you go to Bios setup load setup defaults and set the proper settings for Voltage and timings DDR667 at 2.1 Volts and enable the remap setting and then let it boot to a boot disk from http://www.memtest.org and see if it see's the correct size of ram.

 

 

I have talked to Asus a few times, and they're the ones who sent me here in pusuit of RAM timings. I have not tried different video cards, which is not really possible, since I don't have any other PCI-e bus cards here- they're all AGP and of course, this mobo doesn't have an AGP slot. My current hypothesis is that there is a conflict between the Corsair RAM that I have (the model, not the specific sticks) and this motherboard. Others have used 4GB of non-Corsair successfully with this mobo and my BIOS rev, and of course, 2GB of this ram works just fine. I haven't read of anyone else on any forums using these sticks at 4GB with this mobo. Everyone else is correctly using 2GB and running WinXP Pro.

 

I'm going to post some stuff on the Asus forums and will likely be quoting from this thread and my email with Corsair extensively. The best solution would probably be a conference call!

 

Thanks,

knobbicus

[Yellowbeard]

Actual Memory = 4096

Memory in Bios = 3584

Difference = 512

 

Any chance you have a single 512mb video card or 2 256mb cards installed? If so, RAM GUY's reference to the PCI caching may be spot on.

[RAM GUY]

Doing a conference call is no problem, they know how to get a hold of me personally I have known most of the people there for many years!

 

And there is not any way for a MB to be module maker specific or to single out one module maker over another the memory will be made with in certain guide lines that prevents that from happening or it would not work at all!

Like I said you either have a configuration limitation issue or a problem with the MB and or Bios. I would suspect its just the currant configuration. Testing the system with another Video card would be important in this case if you can barrow one.

 

P.S. Its no secret that MSI Video cards and ASUS have had some history in the past! So again if you can get your hands on another Video card even a PCI Video card just to test would be a big help!

[tasii]

Hi Knobbicus (and all),

 

It would appear that I have a similar situation with similar components.

To wit:

 

ASUS P5B Deluxe/WiFi-AP Bios v.804 (10-24-06)

E6600 Core 2 Duo Model BX80557E6600 Retail

4 Gig Corsair TWIN2XP2048-6400C4 (2 matched 1gig pairs)

BFG Tech BFGR76256GTOCE GeForce 7600GT 256MB 128-bit GDDR3 PCI-E

 

I am currently running XP Pro 32-bit. I originally had 2 gig installed and opted for the additional 2 gig after realizing satisfaction with the first set. I will say that it was a bit disconcerting after installing the 2nd pair yesterday and only showing 2.93 gig in system properties upon boot-up.

 

I called Corsair who later left me a message saying that this issue had been addressed in their forums. A few searches later, here I am.

 

The difference between what BIOS reported your RAM to be (3584 MB) vs. what mine was saying (3008 MB) confused me. Reading on and seeing the reference to the "Enable Remap" option in BIOS, my reported size now recognizes 4096 MB (in BIOS). However, Windows now sees only 2.00 GB in system properties. How is this explained I wonder? Am I to presume that Windows is only making use of half the installed RAM?

 

Anyhow, I will monitor this thread to see how it unfolds and if you and/or the Corsair folks have any new information on this, I would greatly appreciate it.

Also - can you link to any forum (or other) activity which you are persuing on the ASUS end?

 

Thanks,

tasii

[RAM GUY]

Widows in its 32 Bit Version WinNT, Win2K, WinXP will not see more than 4 giga bits of memory and no application will be allowed to have access to more than 2.0 Gig of memory. That is normal. There are some hacks you can try to force it to use upto about 3 Gig but you would need to use a 64 Bit O.S. to see more than 2.0 Gig of memory in Windows.

 

BIOS sees 4GB, Windows sees 2.96!

Example:

4-1,0 Gig = (4096) Giga Bytes X 8 = 32,768 M-Bits

Any 32 Bit O.S. or Chipset will only see 32,000 M-Bits

Then it would have to subtract any other memory used in the system like for your Video card and or cache on your CPU, LAN or Modem, and the MB bios may reserve some for caching as well. That would make the total size of memory accessible to your system, something between 2.6 to 3.2 Gigs of available memory.

[linnewbye]

Hello there, i've been encountering the same issue, I have 4 sticks of corsair memory (VS1GB667D2) and the BIOS reports only 3008MB. I'm also running windows XP SP2 32bit version and it shows 2,93 GB. I will try the enable remap option and post here tomorrow, i don't know the BIOS version yet as i'm not home right now.

 

 

ASUS P5B Deluxe/WiFi-AP

Core 2 Duo E6300

4 x Corsair VS1GB667D2

Gainward BLISS 7950GT PCX 512 DDT

2 x Seagate Barracuda 7200.10 (ST3320620AS)

LG GSA-H22N (black)

Sirtec HPC-500-A12S 500W

Creative X-FI MX Extreme Audio retail SB0790

Samsung Syncmaster 960BF 19 inch 4ms white