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Hp Z 400 mixed ram

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Hp z400
Microsoft Windows 7 (64-bit)


I have 8gb ram  " 4x2gb"  installed on my Z400 6 dimms slots  I want to upgrade to 16gb can i use 4x2gb sticks  with 2x4gb sticks ?


this one already installedthis one already installed

the one i want to get


this 1 i want to buythis 1 i want to buy

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The Z400 is equipped with two banks of triple-channel RAM slots. Ideally, you would have two sets of three identical RAM sticks. In your case, you have two of one kind and four of another, which isn't ideal but worth some experimenting.

If it was me, I would load slots 1, 2, and 3 with three of the 2GB sticks. Then load 4, 5, and 6 with the remaining 2GB stick and the two 4GB sticks.

Not sure what it's going to do with the mismatched DIMM in the second bank, but it's worth a shot. Run some benchmarks and see what gives the best performance. For instance, what happens if you remove the odd man out and leave 3x2GB and 2x4GB? The 2x4GB should run dual-channel while the 3x2GB run in triple-channel.

Below is a diagram of the slots for your reference.





HP Z400, W3680, 6x8GB 12800, RX 570, 250GB WD Blue NVME, Pop_OS Linux
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