System says I have over 16gb memory available when I only have 8gb of RAM

bloodnickel1

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Jul 7, 2011
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See title. This is weird to me. I'm not super computer literate though. I recently replaced 2 8gb sticks with 1 new 8gb stick because they were faulty. Dxdiag/nvidia/task manager all say I stilll have 16gb of RAM. Have I fllubbed something up?
 

bloodnickel1

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Jul 7, 2011
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18,510
CPU-Z says 16gb as well... But I just got it in the mail and even the invoice confirms it's 8gb like I bought. Not "8x2" or anything like that, just... 8. I guess they may have sent me the wrong stick on accident?