BIOS/Windows recognizes half memory

[lorum]

Hello all,

I'm having problems with my memory. To clarify, here's the problem:

- BIOS recognizes 2 GB
- Windows 7 recognizes 2 GB

- CPU-Z recognizes the full 4 GB though.

Specifications:

ASUSTeK Computer INC. Rampage II GENE Rev 2.xx
OCZ 1333 2x2GB DDR3 (OCZ3RPX1333EB4GK)
2.67 gigahertz Intel Core i7 920 (O.C. to 3.2)
Windows 7
ATI Radeon HD 4870 X2

I had Windows Vista installed before I installed Windows 7, but that would hardly explain why the BIOS only recognizes half of my memory...

 

[Mongox]

Lorum, when I answered above about checking the RAM voltage I hadn't learned as much as I know now about the i7 and its standard of nothing higher than 1.65V. I was just wondering in another thread about why anyone is still making higher voltage DDR3 RAM.
http://www.tomshardware.com/forum/263626-30-corsair-xms3-reaper-edition-triple-channel

OK sounds good, You're right, I was looking at the duals. But I wasn't aware that ALL triple channel RAM was 1.65V either. So if they make 1.9V dual-channel, do they make 1.9V 3-channel?

Makes you wonder why anyone would make 1.9V DDR3 RAM anymore at all. I see so many issues related to voltage requirements in this forum, even with DDR2. Maybe Intel's standard will force all companies into tighter standards. I suppose that 2.2V say is cheaper to manufacture?

But it seems clear that from the user's standpoint, 1.8V-2.0V for DDR2 and 1.5V-1.65V for DDR3 would make a lot of sense. And would reduce the need, and demand, for such a wide variety of modules.

Had I remembered this thread before, I could have emphasized the voltage thing again and helped you save some time, so sorry for that. But great that you found a solution!

I guess again, this points out the problems of manufacturers making ANY DDR3 that's over 1.65V. And answers the question of what happens if you do put non-i7 type DDR3 into an i7 board --- odd things.

Another thing that's odd is that I keep seeing the statements in motherboard manuals about "Intel doesn't allow/recommend use of RAM higher than 1.5V-1.65V, etc..." immediately followed by the motherboard's list of approved RAM, most of which specifies higher voltages - and those voltages listed right in the manual as above 1.65V!!!!

 

[nabilalk]

Just installed Windows 7 with an Intel (R) Core(TM)2 CPU 6400 @ 2.13 GHZ, 3.20 Hgz

Installed memory accd to System is 4.00 GB with 2.94 usable.

64 bit operating system.

It says that about 1GB of the memory is being reserved for the Bios and drivers for other peripherals. So Windows recognizes the 4GB but is only letting me use about 3GB. Any solutions? It seems others have had issues with their BIOS or the memory module itself. Mine seems to be software related. Any thoughts? Thanks!

 

[Shiggaz]

Im confused! I have the exact same problem Lorum had. You say he fixed the problem but nowhere do i see or understand how he fixed the problem? Does this mean he set his voltage higher than 1.65 or just got new RAM? I currently have an i7 920 with 6gb Corsair XMS3 Triple and i cant get 6gb ram to show in windows 7 only 4gb but CPU-Z shows 6gb! I have the Asus-P6T Motherboard and also there is no DRAM option as said in another post. Its quite frustrating having 6gb and only being able to utilize 4gb! Memory test also show my ram sticks are fine and i have also tested them all 1 by 1 and all good.

Any help would be greatly appreciated!

 

[briligg]

shiggaz - i too have this problem, on an asus rampage II gene. this thread is listed as solved though, so i am going to start a new one, or the wise ones aren't going to check it. the thread will be called '6gb ram installed, 4gb working'.

up to this point, i'll tell you what i know. core i7 is designed for ram of no higher voltage than 1.65v. if people have ram that is not designed for that voltage, they can undervolt it and adjust everything so it runs stably (which it may well not do no matter how much adjusting they do), or they can run it at stock and put extra cooling on the cpu, and probably the north bridge too, so they don't overheat, or they can go out and buy ram designed for their system.

asus boards have occasionally been having this problem. you may be able to return your board. i would return mine, but i bought it out of country and so i can't. the moderator in the asus forum for the rampage ii gene blamed my problem on the fact my ram is not on the qualified vendor list for my mobo. the store says other customers have had no problems with the ram, and that it is low voltage, as specified. however, it is not xmp memory. if i could do it over again, i'd buy xmp memory from the approved list in the mb manual. but i can't. (permit me to whine.)

some people say that occasionally the pins on the mobo get a little bent, and the connection to the cpu is bad, and that interrupts communication with the ram. they carefully unbent the pins, and the problem went away. but my pins seem to be fine, and i still have this same problem. someone, somewhere on tom's, said they solved it by adjusting their 3rd party cpu heatsink, which wasn't properly in place. i'm trying to find that thread again.

hope to see you on the new thread.

 

[Guest]

I had the same problem with an ASUS P7H55-M Pro with an I5-750 CPU and 8GB memory. I originally had 4 GB DDR3 Dual channel (2x2GB) and thought the memory was bad so I bought 4 more to try. 4GB showed as 2GB and 8GB showed as 4 in both the bios and Windows 7(actually windows sometimes showed 8GB was installed but only 4 was usable even though the bios always showed 4GB usable). I tried everything and searched all the message boards to no avail. Most posts point toward either a badly seated CPU or a bad motherboard trace between CPU and Memory. I reseated the CPU several times to no avail. I was about ready to give up when I decided to try the CPU one more time. I checked the socket and blew it out with air. Then I had read about a Japanese post about applying lateral pressure on the cpu (away from the locking point of the lever and towards the pivot point of the lever) as you close the CPU. I had recently got COD4 Multiplayer running on 64 bit windows 7 by plugging in a microphone, so I was willing to try anything. I applied firm lateral pressure in the indicated direction while closing the CPU holder. I also made sure the headsink was installed with even pressure. Unbelievably, this worked and the bios reconized the 8gb. Hope this helps. Not sure why ASUS motherboards seem to be more susceptible to this issue.

 

[asdf_31]

I've spent a week on this problem. Same symptoms as above:
windows saw 8GB total, 4GB hardware reserved.
BIOS showed 4GB
CPU-Z, memtest both showed 8GB
No progress seating individual dimms, rearranging dimms, etc.

I just tried reseating my CPU and that fixed it. Unbelievable.

 

[harryhill]

I have Win 7-64 and 6GB shows as 2.99GB-EFI BIOS shows 6GB.
But...I also have Win-8 and it shows 6 GB. Also, Ubuntu shows: 6GB. All on different partitions.
To me, it seems like an OS problem.

 

[harryhill]

Ooops...Win 8----64.

 

[nikorr]

This topic has been closed by Nikorr