Can 8GB and 4GB of the same memory be used together

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It often works just fine, and Intel chipsets since 2004 will even run in flex-memory mode where the 1st 8GB is in dual-channel and the last 4GB in single-channel. AMD tends to be a bit pickier and drops to single-channel only but still usually works fine with it.
It often works just fine, and Intel chipsets since 2004 will even run in flex-memory mode where the 1st 8GB is in dual-channel and the last 4GB in single-channel. AMD tends to be a bit pickier and drops to single-channel only but still usually works fine with it.
 
Solution