I also use an HP Compaq Elite 8300 CMT with Windows 10.
Win10 is not officially supported, but it works fine
Because I am planning to install an SSD, I wanted to update the BIOS.
The original BIOS version was V2.05 (from 2012), which I have now updated to v02.90 (from 2013), from the Win7 64 bit version on the HP side
There is also a significantly newer BIOS version v03.05 from 2019, but in order to install it, the version v02.99 must supposedly first be installed.Unfortunately, this version v02.99 can no longer be found in any of the operating system folders for the HP Compaq Elite 8300 CMT, although according to the description of this user it must have been there earlier.
Here he describes that he successfully installed versions v2.9 -> 2.98-> 2.99-> 3.04-> 3.08 one after the other, which he downloaded from the Win7 / 64bit folder.
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