Glad it worked after Nic's recommendations.
Please bear in mind OpenCL is available up to version 1.2 and this is enabled once you install the latest video drivers for your graphics controller.
See the following information about product features:
right now my driver version is:
Product Detected Intel® HD Graphics 4000 Current Driver Installed 10.18.10.3496 Your driver is current.
but Davinci still told me that:
and details of my computers:
Hope the Chinese doesn't bother you
Thank you again for the advice, and I will also look for support from Blackmagic.
Thanks for coming back to the communities.
OpenCL driver is installed once you load latest video drivers; see release notes for more information:
Please try contacting your software developer for updated patches or software updates.