PeterSchwatz75,
The z640 specification for Xeon E5 v3 processors includes CPU's up to 18 cores and 145W:
https://www8.hp.com/h20195/v2/getpdf.aspx/c04400040.pdf?ver=1.0
I don't see a listing for the Xeon E5-2698 v3:
https://ark.intel.com/products/81060/Intel-Xeon-Processor-E5-2698-v3-40M-Cache-2-30-GHz-
> but that is 135W and is within the power range supported. However, on Passmark Performance Test baselines, of the 154 z640's tested, there are no z640's using the E5-2598 v3. I would advise against considering it.
The highest Passmark result for CPU performnace in the z640 is 24576 sing a pair of E5-2667 v3 8-cores. No. 2 on the list is E5-2667 v4 at 24234. The E5-2667 has always been a good performer, the v2 as well. The balance of clock speed to core count seems to me to be about the best with 8-core processors. In a z620, results are very good using an E5-1680 v2 8-core overclocked to 4.3Ghz
As all the motherboard listing in Pasmark results call it "212A" , it's nearly certain that the BIOS must be updated to accept v4's. Research that carefully, and especially the method to make the change.
Passmark CPU ratings are loosely a relative description of the number of total clock cycles per unit time, but choosing a CPU is more involved than that. Look into the applications you're using with the goal of understanding how well the principal programs are multi-threaded, whch are more dependent on single-thread performance, and which can or can't use multiple preoceeors. In server, compute, and simulation, the core count can be more important, but in visualization, 3D CAD, and animation, the single thread predominates. Also, some software does not work on multiple processors- Adobe products for example, and others don't recognizr multiple GPU's such as Autodesk. There are some useful articles on these subjects on the Puget Systems site.
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