12gb ram but only 9.97 usable

[Tom-T9]

Hey! The title says it all. I have 2x4GB 1866MHz RAM, and installed 2x2GB 1333MHz RAM as well. System says I have 12GB RAM, but can only use 9.97. My question is, does it worth to have two 1333MHz RAM near the two 1866MHz RAM modules.

I'm running Windows 10 (64-bit).

 

[Lutfij]

1| Don't mix and match rams, they are more harm than good. They will show up probably as a total amount of ram available but in reality they are based off a different batch of silicon(if they are from the same brand) have different internal timings and the last stated point is their mismatched frequency's resulting in degraded performance overall.

2| No matter which config you put it, there is still two sets of rams that operate on two different frequency's. I'd advise on removing the 2x2GB 1333MHz kit from your system and see if all the ram is available for use+you may see a boost in performance.

On that note, might I ask you full systems specs(inclusive of the ram kits sticker specs)? To rule out onboard graphics chip allocating ram for itself...?

Are you sure your BIOS is upto date and that the kit is installed in their appropriate channels for proper dual channel configuration?

 

[Tom-T9]

1| Don't mix and match rams, they are more harm than good. They will show up probably as a total amount of ram available but in reality they are based off a different batch of silicon(if they are from the same brand) have different internal timings and the last stated point is their mismatched frequency's resulting in degraded performance overall.

2| No matter which config you put it, there is still two sets of rams that operate on two different frequency's. I'd advise on removing the 2x2GB 1333MHz kit from your system and see if all the ram is available for use+you may see a boost in performance.

On that note, might I ask you full systems specs(inclusive of the ram kits sticker specs)? To rule out onboard graphics chip allocating ram for itself...?

Are you sure your BIOS is upto date and that the kit is installed in their appropriate channels for proper dual channel configuration?

Thank you for your reply. I actually managed to buy 4x4GB 1666MHz RAM, because for some reason 4 sticks of 1866 MHz RAM were too much for my motherboard to handle, even tough in the description it says it could handle 2400 MHz RAM sticks on CO. Anyway, thank you for your helpful comment, will re-visit this page if I'm facing with a similar problem.