Cracking Open HP Z820 Workstation: Power supply cooling fans

I am using the z420 model and run CATIAv5, PTC/ProE, Creo Parametric, UGNX with absolutely not issues. This line of workstations have impressed me so far with how quite they are, and how much computing power they come with for the price.

mwclake1 concerns about customs parts is valid and it is for that reason that the true number of PC sales is skewed. There is large number of independently built computers, which is why accurate new PC sales are not and cannot be correctly accounted for. It is therefore likely that the post PC projections a very wrong indeed.

I like the design, for a major brand.
However I have been bitten real bad many times from custom parts from the major manuf trying to do replacement parts and/or upgrades that I only customs build my own personal PC's myself now from standard components so easy to replace, cheaper, and can upgrade the way I want with common parts and not be held hostage by over priced upgrades or like one time was promised to be able to upgrade CPU's later when bought one Dell I had, very soon after buying the workstation they discontinued it and never offered the upgrade option afterwards.
So as good as that one seems, I am going to stick to building my own again for my next upgrade. But for many who do not, seems like a good choice for a high end workstation.