Win 7 Ultimate 64 bit only recognizes 4GB of 8GB of installed RAM?

[VGM10000]

I just installed Win 7 Ultimate, 64-bit on my new build, and I cannot figure out why the OS only sees half of my memory.

I ran memtest to ensure that all the sticks were working fine, and after 4 runs, I got no errors. Ive also used the pairs individually before, and I have never had any problems.

Also, when I try to get a System Rating ("Windows Experience Index"), the OS spits out an error that "The Windows Experience Index for you computer could not be computed... The assessment or other operation did not complete successfully. This is due to an error being reported from the operating system, driver, or other component.", and it seems to be hanging on the "Assessing Disk Performance" stage of getting a score. I figure it might be related.

Ive gotten Vista 32-bit to work fine and it got a 5.9, although only 3.4GB of memory was recognized (obviously).

Since I have installed all of the drivers, I am thinking it might be a BIOS issue, but I don't know what to change. Anyone know what's up?

The build is:

Intel i7 860 OC'd to 4.01Ghz
GeForce GTX 285
Gigabyte GA-P55-UD4P
2 Kits of GSkill RAM. 4GB each
WD 750GB Caviar Black HDD
Antec P183 Case
OCZ 700W PSU
LITE-ON DVD/CD Burner

-VGM

 

[bigfysh3]

Does BIOS recognize all of the RAM?

 

[alextheawesome]

Go to the start menu and type in msconfig. go to "boot" tab. clicked "advanced options." Does maximum memory say "4GB"? I've heard of this being a problem with some people. But also make sure to check the BIOS.

 

[VGM10000]

Does BIOS recognize all of the RAM?

I feel like an idiot!

It sees all of it but only the first 2 slots are enabled. How do I enable the other two?

 

[False_Dmitry_II]

That part is what motherboard manuals are for. I've never seen such a thing, so I couldn't tell you what it is without doing that myself.

 

[VGM10000]

That part is what motherboard manuals are for. I've never seen such a thing, so I couldn't tell you what it is without doing that myself.

Ive scoured mine but I cannot find anything on enabling dual-chanel. In the section where it explains how to install the memory it hints that you can use dual-channel when it is "enabled" but there isn't an option that I can find in the BIOS, nor any mention of it in the manual.

I feel like it should be doing this automatically, but then, wouldn't it? The MIT tweaker overview shows that it detects all 4 sticks and that only two are active, which again suggests that there is some sort of switch.

I am really confused as to what to do! I don't want to wait any longer to use my full 8GB!

Ill continue to look but someone probably knows something I don't.

 

[alextheawesome]

Found this thread. http://forums.anandtech.com/showthread.php?t=323715 As taken from problem being solved by original poster

"Ok guys... problem solved!

I saw several similar threads around the web and noticed that while many different MB makes and models were affected, a lot were running the same 8 GB 1600 DDR3 package from Corsair I was... returned the memory for a set of 1600 DDR3 Gold Dimms from OCZ and POOF - problem gone.

FYI, memory did not error out using Memtest... no crashes... just this odd problem that was fixed by changing the RAM. "

 

[VGM10000]

Found this thread. http://forums.anandtech.com/showthread.php?t=323715 As taken from problem being solved by original poster

"Ok guys... problem solved!

I saw several similar threads around the web and noticed that while many different MB makes and models were affected, a lot were running the same 8 GB 1600 DDR3 package from Corsair I was... returned the memory for a set of 1600 DDR3 Gold Dimms from OCZ and POOF - problem gone.

FYI, memory did not error out using Memtest... no crashes... just this odd problem that was fixed by changing the RAM. "

Thank you for finding the thread! Ironically I looked at that set of memory while making the purchase.

However, I bought two 4GB kits of GSKILL RAM, so I don't know if there are any widespread issues with the particular branding of memory. I'll look into it.

 

[VGM10000]

Just as an update as to what I have done to troubleshoot this problem:

I tried reorganizing the memory in every way I could imagine, and I figured I wouldn't get anywhere because all the slots are filled anyway. As expected, nothing happened.

I also tried running the memory at it's exact rated specifications (I have them clocked a bit higher then retail) but that diddn't seem to do much, either.

I checked CPU-Z and it says the memory is running in single channel so I am near positive I have to tell the motherboard to run in dual-channel, but I just need someone with a GA-P55-UD4P to tell me how to do this.

Please help! Thanks to everyone who has already provided suggestions and leads.

 

[VGM10000]

Ive found online by now that this seems to be more of a physical motherboard issue than anything else and that many people with the GA-P55-UD4P are having issues with their memory. It has to do with either defects in the memory slots or bent pins in the CPU socket.

In any case, I am going to re-post this in a more related section. Thanks to everyone who helped out!

 

[Yaman Bisht]

U must check whether it is windows7 64 bit b/c only 32 bit have problem of ram for 8gb u should check the memmory slot working properly or not or ur ram have no manufacturing defect