Sabertooth 990fx 2.0 & HyperX 32GB 1866MHz only 15.9GB available

[reverse_rebirth]

Hi there,

I've spent a fair bit trying to figure this out on my own and piecing together options from previous posts but I honestly can't get my ram to work at full capacity.

My specs:
Windows 10 Pro 64bit
AMD FX-8350 4.3GHz
4x 8GB Hyper X 1866 MHz CL10 RAM
Sabertooth 990fx 2.0 (fully up to date bios)

I've got a feeling I'm likely not setting the dram and voltage correctly and auto optimizing etc doesn't work either but think is it possibly that 2 of the sticks are stand alones whereas 2 of them are part of a kit of 2 (though any combination of the sticks work perfectly fine for 16gb).

I've already gone through with msconfig to see if it was windows limiting it but even in the bios it states 16gb despite showing all 4 sticks and their clock speeds if I go into the north bridge settings.

If anyone could point me in the right direction and save me having to send back the 2 sticks and/or having to replace parts that would be appreciated

 

[kanewolf]

Cut the clock speed of the RAM. 4 DIMMs are notorious for only working at 1333Mhz on AMD FX CPUs.

 

[reverse_rebirth]

Cut the clock speed of the RAM. 4 DIMMs are notorious for only working at 1333Mhz on AMD FX CPUs.

Okay cheers, will try with underclocking to 1333Mhz then.

EDIT: No dice sadly, hasn't made any difference to the amount of ram used.

 

[Calvin7]

FX-8350 supports 1866MHz memory speed with one DIMM per channel and 1600MHz memory speed with two DIMMs per channel. Higher frequencies require overclocked system.

Memory is guaranteed in the form sold. Other combinations you happen to create have no guarantee to be compatible together. You are free to do your own compatibility testing. What is guaranteed is using a single kit.

 

[reverse_rebirth]

FX-8350 supports 1866MHz memory speed with one DIMM per channel and 1600MHz memory speed with two DIMMs per channel. Higher frequencies require overclocked system.

Memory is guaranteed in the form sold. Other combinations you happen to create have no guarantee to be compatible together. You are free to do your own compatibility testing. What is guaranteed is using a single kit.

Well I purchased a full set of Ripjaws Z at 32GB 1600Mhz and it still won't run more than 16gb.

 

[kanewolf]

Have you tested to see which of the four slots work together?

 

[reverse_rebirth]

Have you tested to see which of the four slots work together?

I have not, silly question but how would I check bar booting with 2 at a time? I guess is it possible that the board is on the fritz?

 

[kanewolf]

If it were me, I would start with 1 DIMM. Test all four slots by moving the DIMM from slot to slot between boot cycles. Verify that all 4 slots work individually. Then I would try the two black slots and then the two tan slots with two DIMMs.