Coreelec not booting from sd card

Dear Colleagues,

I’ve bought a 32gb Micro SD Card for my Tox3 (s905x4) box.
The card is an integral Class 10 A1 high speed card.
I used Rufus to burn the image to the card, copy and pasted the sc2_s905x4_4g_1gbit file from device trees to the root of the card and renamed it dtb.img.

I inserted the card in the box. Pressed the reset button and powered it on. I held the reset button for over 30 seconds but the screen was still black.
I then started at the beginning again. Used the same card, but this time used ‘Etcher’ to burn the coreelec iso image to the card. Inserted in the box, used the toothpick method but still a black screen?.

Is this the card at fault? Or shall I just get a Sandisk card and re-try ?.

Any help is appreciated.