Question I installed new RAM (32GB) but only 16 is being detected?

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May 21, 2019
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Hi there. Recently I installed new ram (https://www.amazon.com/gp/product/B0123ZCAKW/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1) but not all of it is being detected. I physically installed 32 GB in total, but both my BIOS and windows shows that only 16 are being used. I'm not sure if my motherboard can't support this much RAM or what, but I could really use some help on this problem. My motherboard (according to CPU-Z) is the Gigabyte B150M-Gaming-CF. Also, I tried switching the memory profile in my BIOS to 2133 (to utilize the full speed of the sticks), and it seems like it works in BIOS but when I save and reboot into windows, it says that the sticks are only running at 1066, which is what the default RAM was running at. Here's a picture of my BIOS, showing not detection of the other two, 8gb RAM sticks:

image0.jpg


Any help would be greatly appreciated! If you need me to provide more pictures/information, please ask!
 
So when I bought the RAM, it came in packages of two 8 GB sticks. I'm just use two packages to provide 4 sticks of RAM that are all completely the same. Are you saying I should have bought one package containing four sticks? Appreciate the explanation.
Yes. Buying two sets of 2, are not matched for 4 DIMM slots. You have to get a 4 Sticks. I wioll give you an example. I have 4 sticks of GSkill Ripjaws DDR4. The Numbers are as follows ( the first 10 numbers are identical and it is the last 5 you need to look at). I put the slot arrangement next to the numbers to show how it should be configured.
12969 - A!
12970 -B1
12971 - A2
12972 -B2
 
May 21, 2019
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1
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Yes. Buying two sets of 2, are not matched for 4 DIMM slots. You have to get a 4 Sticks. I wioll give you an example. I have 4 sticks of GSkill Ripjaws DDR4. The Numbers are as follows ( the first 10 numbers are identical and it is the last 5 you need to look at). I put the slot arrangement next to the numbers to show how it should be configured.
12969 - A!
12970 -B1
12971 - A2
12972 -B2
Oh man. So do you think that's my problem? AKA the reason why my PC is not detecting all 4 sticks is because I didn't buy a 4-pack? That would really be a shame lol. But if that's the solution that would make me feel better as opposed to the problem being something with my PC.
 
Oh man. So do you think that's my problem? AKA the reason why my PC is not detecting all 4 sticks is because I didn't buy a 4-pack?

Did you try any of suggested tests from before?

Test with single ram module. Try it in all slots.
If it works in one slot and doesn't in another, that could mean bent cpu socket pins.

Test with all modules (one by one) to rule out defective ram module.
 
Oh man. So do you think that's my problem? AKA the reason why my PC is not detecting all 4 sticks is because I didn't buy a 4-pack? That would really be a shame lol. But if that's the solution that would make me feel better as opposed to the problem being something with my PC.
Pretty sure that may be the issue. Tried to make is as clear as could using four sticks I had. Those came from my last configuration. I have since Upgraded and only using two sticks. having said that, using what I put up there, lets say you bought TWO matching sets. Okay say one is 12969 & 12970 and the other is say 12974 and 12975. If you put 12969 in A1 and 12970 in B1 and 12974 in A1 and 12975 in B1, those are NOT a matched set of 4, but two Separate matched sets. They MAY work, but more often than not will give you problems at some point. Granted, four stick sets are pricey. I went with a two set of 16gb sticks for 32gb rather than a 4 stick set of 8gb.
 
correct 4x8GB kit is not the same as 2 kit of 2x8GB
Omg people not true, you can run 2x8 and 2x4 if they have the same frequency and latency and dual channel is running without any problem. OP, 2 sets of 2 sticks is perfectly fine, this is not your problem. A friend of mine is running the configuration i gave an example, he is running 2x2gb adn 2x4gb dual channel is active he doesnt have any issues. sets of 4 sticks is used only in quad channel, there are sets of 6 sticks for 6 channel(server cpus) and sets of 8 sticks for 8 channels(again server cpus). For a period of time i was running 4x8gb and 4x4gb, a total of 8 sticks without any problems because they were sets of 4 sticks guaranteed to work in quad channel. If what are you saying si true then i should look for sets of 8 sticks? I gave up on the set of 4x4gb because a stick failed after 1 year and half and it was in warranty period, i preferred to take my money back because ram prices really skyrocketed and cant afford another set of 4 now.
 
May 21, 2019
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Omg people not true, you can run 2x8 and 2x4 if they have the same frequency and latency and dual channel is running without any problem. OP, 2 sets of 2 sticks is perfectly fine, this is not your problem. A friend of mine is running the configuration i gave an example, he is running 2x2gb adn 2x4gb dual channel is active he doesnt have any issues. sets of 4 sticks is used only in quad channel, there are sets of 6 sticks for 6 channel(server cpus) and sets of 8 sticks for 8 channels(again server cpus). For a period of time i was running 4x8gb and 4x4gb, a total of 8 sticks without any problems because they were sets of 4 sticks guaranteed to work in quad channel. If what are you saying si true then i should look for sets of 8 sticks? I gave up on the set of 4x4gb because a stick failed after 1 year and half and it was in warranty period, i preferred to take my money back because ram prices really skyrocketed and cant afford another set of 4 now.
My friend told me the same thing. I don't understand why 4 sticks that are virtually exactly the same would not work. I even got the sticks to run at their maximum potential speed of 2133 MHz by enabling XMP. That being said, I cannot for the life of me figure out why my motherboard and Windows 10 will not detect all 4 sticks totaling to 32 gb.
 
One thing you must consider, you have 2 sets of 2 sticks, be sure to do not mix the sticks from the sets, for example i will rename sticks from set 1 s11 and s12 and sticks from set 2 s21 and s22 and you have 2 dual channel configuration, i will name them channel one and channel two. You must but in channel one s11 and s12 and the other channel s21 and s22, do not put on in channel one s12 and s21 and in channel two s11 and s22 or any mix between sets. For a more detailed how are channel configured you must read the manual of the motherboard, the RAM section.