8GB RAM Installed w/ Vista x64, only recognizing 4GB

SpencerL

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Jun 5, 2006
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First of all, thanks for reading. I am running an Asus M2N32-SLI Deluxe mobo with an AM2 3800+ CPU and an evga 8800 GTS 320MB video card.

I recently upgraded to Windows Vista Home Premium x64. I purchased 4x2GB RAM and installed it *after* installing Windows. (I was using 2GB previously, which is now in another computer)

In the BIOS, the total memory is listed as 8GB, but the available memory is listed as only 4GB. Windows Vista detects 4GB available as well. However, CPU-Z detects all 8GB.

I understand that sometimes memory gets mapped to other devices using MIMO settings, but I don't believe that 4GB should be 'disappearing'.

From what I understand, since both my MB and CPU (AM2 3800+) support 64 bit processing, supporting 8GB should not be an issue.

Can anyone help me figure out what I need to do to get the full 8GB working? I assume this is a BIOS related problem (and not Windows) since the BIOS is only showing 4GB as 'available'. I can NOT find any 'Memory Remapping' options in the BIOS.

Thanks in advance for any help or advice! =)
 
Not much to add except that you need to enable 'memory remapping' in BIOS. On my ASUS p5b that setting is found under 1. 'chipset' 2. northbridge 3. enable "memory remap feature" (if memory serves me, poke around in chipset, you should see it)

According to what I have read your board does support 8 gig and we know your CPU and OS are 64, so there should be no problem.

MOBOs are picky about what they will run when you fill all four slots. So perhaps if one set of memory is single sided and the other is double sided they may not function together? I'm just guessing but read the manual carefully about filling all four slots. Asus usually tells you what kind of RAM you can and cannot use. I see where you purchased a four gig kit so I assume it is identical but still, read the memory section and see if it tells you anything.

I really think your problem is the memory remapping though.

Is Vista telling you 4 gig exactly or what? Vista (pre-SP1) should be telling you 3 gig and change if remapping is not enabled.
 

SpencerL

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Thanks for the responses. I am getting exactly 4GB as available in BIOS, which lets me know that its not the 3 gig issue.

I have checked the BIOS, and

Chipset -> NorthBridge

is where I thought it would be as well.

I'll continue to search for the solution online...but if I can't find the memory remap function in my BIOS (maybe there isn't one?) then I'm not sure what to do at this point :\
 
I found this thread:
http://vip.asus.com/forum/view.aspx?SLanguage=en-us&id=20070825041715562&board_id=1&model=M2N32-SLI%20Deluxe&page=2&count=15

Dude seems to have your board and the same question.

This was the response from Asus:

did contact ASUS and their response is, "The 64 bit OS is designed to work with 4GBs of memory with no problems, please verify that the memory you are getting is tested and approved for use on the board by checking the vendors website."

I guess they meant to say don't worry about a bios memory remap or memory hole option, that does not apply to your motherboard. Buy memory from the qualified vendor list and be happy!
 


Well my ASUS P5B Deluxe/Wifi-App, i doubled the ram to 4x1gb -> 4gb total, it went up an amazing -1mb - windows instead of detecting 2048mb went down to 2047mb - funny thing is, the system feels faster, and even with messing around with vista no luck (this is a 32 bit vista), so im thinking bios update next, i hope i can solve this, or ill upgrade to x64.

Only ASUS boards do this? Show up with half?
 
I have the same MOBO, minus the wi-fi. For the p5b - deluxe the soloution for a 32 bit OS is to DIASABLE memory remapping - that's right, DISABLE. If you enabled it thinking you would need it for 4 gig then that is your problem. I know it sounds odd but that is exactly what happens on my system. Go into BIOS and disable the 'memory remap feature' - it's under 'chipset' > 'northbridge' > memory remap feature (or something worded very close to that)

Of course if memory remapping is already diasbled then you have a different problem.

If you have a 64 bit OS then you do the reverse! LOL

On 32 bit Vista/XP you should be seeing about 3 gig in Windows when 4 is installed. Your BIOS should report 4 but 32 bit will only use about 3+/-.

What does your BIOS report?
 


i already tried it but since i just updated the bios ill try it again...
 

dengamle

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Apr 18, 2007
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with 8 GB installed there should be more than 4 GB usable, with or without memory remapping. If it is a faulty bios, have you checked for a newer version that might resolve it?
 

lp231

Splendid
According to the Asus manual with boards that support up to 8GB. It says if you install 4 pieces of 2GB rams into each slot. Due to chipset limitation you may see less than 8GB, but less that half of the amount you install definitely tells there's something wrong. Maybe a update to your bios may solve this issue. Or is it possible that you exchange the brand name of your ram with a friend or at a computer shop to see if it detects the full 8GB?