HELP! - Raspberry Pi issue (for RGB-to-HDMI)

[Violo]

Hi,
I'm having a problem with my Raspberry Pi configuration and I'm not sure if it's my fault or if the device is defective.

After trying to install the operating system (Pi OS), two Kingston SD cards seem to have become corrupted.
They are now unreadable on any PC (Windows, Mac, Amiga), and the Raspberry Pi shows no output on the screen.

I would be willing to send my Raspberry Pi and the SD cards to anyone who can help me test them, and I'm happy to pay for the support.

Thanks

 

[Robofruit]

Hi, which software are you using to write the image? Have you reformatted the SD cards and if so do they then appear in Windows?

You could have defective SD cards, they may be fakes.

 

[Violo]

Hi,
i used the Pi software downloadable from the Pi web site.

I cannot re-format the SD cards because they are not readable from any computer. Is the same i haven't inserted any SD. Nothing to click or for to see details/properties.
When i bought, the SD were readable, i could flash them with the Pi OS. After they were used on the Pi (receving black out signal) thy became unreadable from any computer.

Two of two SD corrupted?... i think is quiete strange