Your post Falconet put more water under the bridge for my statement that WCG for Windows sucks and the grid dont run efficent as it could due to it must have most Windows machine.

My NUCs just run OET, UGM and MCM projects and they mostly get MCM works. Even if MCM stood out as slowest project under my Windows test week Ubuntu was ahead or close even, but never slower in those three projects. I dont do all project on the NUCs because 33+ hours works is lackluster.

My i3 and i5 does all projects but both of them is Windows 10 machines so have nothing to compair with in the same way as identical hardware as with the NUCs. Whats why I did the test week with them (beside that the NUC is barebone and I had too give the new one an OS anyway).

"Only 8% of total hosts are active"
What is even bigger waste then run slow on Windows.

But I guess what previous installation on devices not longer in use counts in too. Like I have 10 installations but only 4 is in use now. Rest of the 6 is phones what had died and been replaced or computers what been replaced too.

But i can see the problem with non activity too. For exampel my team has nine members only 2 are active at precent. 4 of them have never done any work at all just signed up.

The reason for this huge difference should be found within the operating system architecture.
Since decades, Windows design is poorly efficient comparing to *nix.
Working in the industry since close to 30 years, I always fight - as far as possible - for relying on Unix/Linux systems for time critical and performance critical applications instead of Windows systems.
You can easily notice that the memory management is far away to be efficient by Windows systems.
Regardless of the OS memory foot print (which is anyway higher by Windows XP/7/... than by Linux), you can observe how much memory is required per WU (respectively per boinc thread) by Windows and by Linux.
For OET1, 8 threads including OS take < 0.9 GB RAM on Linux Mint 17.3 x64, but require about 4 GB RAM on Windows 7 Pro SP1 x64.
The reason for Linux success by Internet infrastructure (service providers, hosters, etc.), should be found at first by resources effectiveness, secondly by system management efficiency and finally by limited license costs.
Over the years, I migrated all my WCG hosts to Linux (Ubuntu and Linux Mint), I have to keep only one Windows system alive for other reasons.
I am currently following the same approach for office environment moving everything to Linux and keeping Windows available using VM for supporting specific application.
Happy crunching on ... Linux,
Yves

Oh so it is nothing to do too make it better i guess then. just stay away fron Windows if care for performance.

About memory use I have also notice that Windows is bad to release unused memory so it takes up more and more over time. Example i ran with 4 days uptime and started with 20% use after 4 days it was up to 25% without I started other programs and with same processes as at start on.
Ubuntu dont do that.