HP Z600 mixes 8GB*4 1333MHz & 4GB*2 1066MHz

[RogerT268]

Hi,

    Currently my HPZ600 with C2 revision has one CPU (Xeon X5650) and 4GB X 3 1066Mhz memory.  I like to add 2nd CPU and  8GB*4 1333Mhz memory.  Can I configure 1st and 2nd CPU with memory 8GB + 8GB + 4GB each, even the memory speed mixed with 1333Mhz and 1066Mhz? The total memory will be 20GB*2.  I understand this is not optimal, but  just do not wanna waste my current 4GB memory DIMMs.

   Would this configuration work? The OS is Windows 10 Pro. 

Thanks,
Roger

[SDH · Accepted solution]

Welcome...

Are you here in the US?  The reason I ask is that eBay buying is a different experience elsewhere and that affects the advice given.

Your X5650 max memory speed is 1333MHz... that is as fast as your Z600 v2 motherboard can ever go also.  So, all your memory should be 1333 or faster.  I have posted here on recycling 1866 MHz 8GB server memory sticks into the ZX20 version 2 workstations and those same sticks will also work fine in a Z600 v2... I've tested that.  But probably not in a Z600 v1 and certainly not in a v1 or v2 Z400 (I tested that).  This has to do with the on-board memory controllers used. About $12-15 USD/stick from eBay.  I use same OEM source sticks in each box, and prefer if they came from a HP server but also have harvested the same ones from Dell/IBM/Lenovo retired server sources.  I've chosen to use Samsung ones preferentially if possible and Micron second if not, and I don't intermix OEM memory types in the same box (but have not had an issue if the same ones come from different server manufacturers).

Your processor only has one sSpec code,  SLBV3, so that makes searching eBay for your second one easy... just search for code.  If there were two (rarely even 3) sSpec codes you'd want to use the latest one if at all possible but that is not an issue for you.

The memory/processor controllers will down-regulate speed of all to the slowest memory or processor component.  Thus you're already throttled to 1066 MHz for all your memory and also will be for both your processors if you proceed that way, and also for your motherboard.  This issue is important for you to consider... you don't want to be pound wise and penny foolish, and you can feel the difference in performance... it is significant.

If you envision upgrading to a used Z620 v2 in the future then that is even more incentive to look at my posts on that 1866 MHz memory I posted on that will be down-regulated to 1333 MHz in your Z600 v2 automatically.  If you'd upgrade instead to a Z640 that family takes different memory.  Memory... it is best to match all sticks and ideally fill all slots.  That way you don't get into rank issues or other more subtle conflicts.  6 x $15.00 USD would get you 48GB of ECC buffered memory that you also could use in a Z620 v2/Z420 v2 later.  We upgraded about 25 Z420 v2 workstations this way with faster 1866 MHz v2 processors and 8GB x 4 or 8GB x 8 that way a couple of years ago, with not one bad stick.

[RogerT268]

Hi SDH,

    Thanks for your prompt response and detail explanation.  There are so many knowledge in your post.  I need to read it thoroughly.  I think I will try my configuration first  (X5650 and 8GB*4 1333MHz + 4GB*2 1066MHz) to see how it performs and determine whether my system does not have sufficient or fast enough RAM.  Then follow your suggestion to get 2 more 8GB later.  My upgrade requirement is to run extra VMware Workstation on Windows 10 and  Apps are not quite CPU intensive.

Thanks again,

Roger

PS: Will get X5650 and DIMM from US Ebay sellers.