Only 4gb out of 12gb showing up

I have 3 sticks of 4gb of ddr3 1600mhz triple channel corsair dominators but when i check bios for them it says only 4gb usable. In windows it says same thing, but CPUZ says i have 12gb...of single channel.

specs:

Mobo: Asus Sabertooth x58
CPU: Intel Core i7 960 @ 3.2ghz (133.64 x 25)

Ive played with the voltages and i just wouldnt know what to do with them, i just know that my dram voltage is at 1.65 as thats what corsair says is needed and QPI/DRAM voltage is on auto but have raised it to 1.5 before still nothin. I read that FSBRAM is suppost to be 1:1 but cpu-z says mine is 2:12. Also says my NB frequency is 3608. Just listing all this stuff cuz ive no clue what the problem is.

Might be that im running 32 bit windows 7 and now 64. But i figured maybe not because bios says 4gb not just windows?

Have you tried resetting the BIOS back to factory settings and then re-tweaking it as needed?

Have you tried only powering up your PC with 1 stick at a time (rotating the sticks out) to see if some of the sticks are not recognizable at all when only a single stick is in?

So are you running 32 bit windows? If so, that is your problem. Dont waste your time checking the sticks. 32bit = 4gb max 64bit = 16gb Windows Home versions, and 192gb in Professional Versions. You'll need 64 bit to see more than 4gb.

He said he "Might be that im running 32 bit windows 7 and now 64. But i figured maybe not because bios says 4gb not just windows?".

Have you tried changing the sticks in the slots? Are they in the correct slots? Update your bios as well to the latest. It's entirely possible you have the sticks in the slots the motherboard doesn't like.

I remember when I put 3x2GB of RAM in a friends computer years ago when X58 first came out; that out of the 6 slots; I put them in the wrong 3. And the system wouldn't even boot. So 1/2/3/4/5/6 as the slots. I put them in 1/3/5. But apparently it was required to be 2/4/6. I didn't work this out until the next day lol. Perhaps your motherboard is only properly detecting a single stick ? If CPU-Z says it has 12 though.. Then I'm not sure.. :\

GoD_tattoo said:

You'll need 64 bit to see more than 4gb.

Click to expand...

Oops, I missed his last sentence. +1 to this.
Even if you get the BIOS to recognize all 12GB, your 32 bit OS will never see more than 4...I think the limit is actually 3.5GB?

I would think your BIOS should still see the full 12GB as it should be agnostic to what OS you're running...

Check out both of these threads for troubleshooting steps...

Asus X58 + 6/12GB memory overclocking - detecting less memory than installed
http://i4memory.com/f54/asus-x58-6-...g-detecting-less-memory-than-installed-19200/

Ram not detected (Troubleshooting)
http://vip.asus.com/forum/view.aspx...1&model=P6X58D+Premium&page=1&SLanguage=en-us

I read that FSB : DRAM is suppost to be 1:1 but cpu-z says mine is 2:12

Click to expand...

At the default BCLK of 133, a 2:12 FSB : DRAM ratio = DDR3-1596, which is what your modules are rated to run at.

Also says my NB frequency is 3608

Click to expand...

The NB Frequency in CPU-Z = Uncore Frequency, and BCLK/QPI Frequency x Uncore Multiplier = Uncore Frequency

I also +1 the BIOS reset. I've had similar goofy issues on some boards because I inadvertently set a setting that disabled memory over 64bits of addressing space (legacy support thing I guess).