E6600 + Vista 64-bit, why only 3GB seen?

bloodandsoil

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Hi, I have an Intel Core 2 Duo, four 1GB sticks of Crucial Ballistix, and a legit copy of Vista 64-bit Home Premium. Yet in my BIOS it only shows 3008MB and in Windows it shows 3007MB. How come my system does not recognize all 4 GB? Thanks.
 

bloodandsoil

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By the way,

I have an Asus P5B Deluxe motherboard (P965 chipset I believe). Not sure if this matters, but just wanted to mention in case.
 

bloodandsoil

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I did. Latest BIOS.

I actually found the solution though. I had to Enable the Memory Remap feature in the BIOS. Now my system and Vista both see 4096MB.
 

BustedSony

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Many motherboards have trouble with four sticks of ram. My P5W-DH also shows 3007 Gigs when four 1 Gig sticks of Crucial are used, even with the latest BIOS. So maybe it's an issue with the 965 and 975 chipsets. However the same P5W properly recognizes the four sticks of OCZ Platinum that are in the system now, and the four Crucial dimms are just fine in an Asus P5K (P35 chipset.)

Yes try upgrading the BIOS, but in the end you may have to switch to different RAM or MB.

How much memory is shown in BIOS has no connection on Earth with the operating system used on the rig, some people seem to have that misapprehension. :??:
 

BustedSony

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That shouldn't be necessary if the two are compatible. The BIOS should show 4 gigs regardless, remapping is for shifting RAM addresses above the PCI Bus boundary.
http://support.microsoft.com/kb/929605
The memory doesn't have to be remapped in my current two systems that have four sticks, the memory is NOT rempped yet shows 4 gigs in Bios and in Vista 64. The other system runs XP and shows about 3.38 gigs. Indeed remapping can cause application and driver incompatibilites with older software. And it's NOT good for XP! Memory remapping versus full compatibility with four sticks seems to be a topic that hasn't been examined.

Oops, an addendum. I checked the XP system and only 3214 megs are showing in BIOS, with remapping it now shows 4096 (3250 in XP) However that unremapped value is different from the OP's 3007 Megs, which is what I had on the other memory, so it goes.... :pt1cable:
 

bloodandsoil

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Well according to the KB article you linked to, one of the requirements of getting the system to recognize the full 4GB of memory is that "The BIOS must support the memory remapping feature."

In fact, out of all of the 4 requirements listed, my system meets all 4. :bounce:

But I read down further about PAE-mode induce driver incompatibility and was a bit concerned. What is PAE? Is PAE the memory remap feature, or is it something different?

PS: Vista 64-bit with 4GB memory is AWESOME :ouch:
 

hassa

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PAE helps expose more then 4GB of RAM on a 32bit OS. Not needed for 64 bit OS.

http://en.wikipedia.org/wiki/Physical_Address_Extension
 

LoneEagle

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I just upgraded from Vista 32 & 2GB -> Vista 64 & 4GB and it is much better. I even reduced to 512 MB the Virtual Memory (Swap File).

I guess SP1 will be even better!
 

kcrush

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This is an old problem that MS should have put out in a regular patch but for some reason has not. Vista (all versions) came out of the box with a problem that in most systems would only recognize up to 3gb. When you put in 4GB you get one of three reactions.

1) Refuses to boot completely/install (most mistake it for other issues)
2) Will load (for some only to safe mode), but will only report 3 gb (common)
3) Will work just perfectly (extremely rare, I think I've read all of two cases where this happend).

The answer is http://support.microsoft.com/kb/929777/en-us.

Download the Vista x64 version half way down on the screen.

Install the patch even if you didn't get that specific error. On reboot you will see 4GB.

Given Vista's voracious appetite for RAM, I really don't know why MS didn't put this in the normal patch cycle so anyone who decided 4GB is the next step will be okay.

Almost forgot to mention. If you fall into the first case, only put 2gb of ram in before you install the hotpatch, reboot fully then shutdown and install the last two 2gb and you'll see all 4.

 

StevieD

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I agree.


Also remember if you are upgrading to 2x2GB that you should install the patch BEFORE you install the upgraded RAM.
 

LoneEagle

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I believe the reason is that update is a fix for some particular configuration. In this case, 3GB+RAM, where most of computer have 2 or less. Trying to patch something not broken, is more dangerous than not doing it. It might cause more problems than solving it.

Hot Fix must normally be installed only if you experience that particular problems, else, do not install it.

SP1 will be soon here and those patch will probably be included and also may be refixed better (and tested).
 

randomizer

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Make that 4 times then. I've installed Vista twice with 4GB RAM installed without a problem.

As for PAE, it is not a replacement for a 64-bit OS. PAE does not expand the 4GB virtual memory limit so applications can still only use a maximum of 4GB. It just allows the system to shove the memory map into the upper end of a 36-bit address range instead of a 32-bit address range and free up the remainder of your 4GB RAM.