Windows Ram and then what's usable?

[militarebear]

Greetings, I thot that since there are some smart folks herebouts that I could post this question. I've been running at it for several days with no luck and it seems that I have read 100s of internet posts. I have 32 gb of ram installed, but windows says that while I have 32 gb installed, only 16 is usable. I attach the following for a quick synopsis:

Motherboard Name:  GA-970A-D3 (3.0) 
BIOS Ver:  FD 
Video Card:  ASUS HD7770
CPU Model:  AMD FX-8350 
Operation System:  Win 7  Ultimate 64-bit SP:  1 
Size:  4 x 8 gb (32 gb) Memory Part No.:  BLS8F3D1609DS1S00 (Crucial 8gb Sport 1600 CL9 @ 1.5 volt)
Power Supply:  1000 Watts
 
Motherboard bios reports 32 gb mem and Windows reports 32 gb installed (16 usable)

Things I have tried:
Complete new install of above windows os;
msconfig/boot/advanced/maximum memory checked and unchecked;
Slowed ram from 1600 to 1333 and back again;
conducted repair install of windows;
removed and replaced ram modules (to include swapping positions);
updated bios (updated to an older one that dealt with memory issue, then updated to most recent one) FD in case you wanted to know;
Ran memtest on all 4 mem modules passed;

Anyone have any ideas how I can get my total usable up to 32??
Thanx in advance. (I'll take the answer off air hahah)

 

[Yoda007]

100% sure you have Win 7 Ultimate? As Home Premium will only see 16gb

 

[htw]

Also (assuming you do have ultimate), if you have not done a new OS install AFTER you physically put in that much RAM, windows will have to be forced to notice/report it. I.e., if you had win7 ultimate with 16 or less, then just shut down, upgraded your memory, then booted... you'll have to do that (unless you reinstall).

It's been that way for a while with windows, I am fairly sure it still is.

htw

 

[rob]

For reference:

Memory Limits for Windows and Windows Server Releases (Windows)

 

[militarebear]

Thanx for the feedback. I did a reinstall AFTER I inserted all 32 gb of mem. I was hoping someone would be able to through me a registry fix or something. I can't figure this out. . . )

Update: I'm left with impression that my mb doesn't accept the dual channel of this particular ram beyond 16 gb so I'm sending it back (two sticks anyway, they said it was too late to return the other two sticks (( ) and ordered a set of 32 which I hope will run in dual channel. I couldn't find what ram is blessed by gigabyte so I'm trying a different company than Crucial. Hope this works out. ))

 

[burdsjm]

You likely needed a different version of Windows.

If you had a beta or early release or hacked copy it would do that.

You could also check your page file to see if the OS was trying to set up a page file for 16gb or 32gb.