You cannot find storage device due to driver of your controller or Disks. because the HW is not compatible.
Check the controller driver and load it during the installation of ESXi, as below
check these sources:
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I'm unable to find Dell Vostro 3470 in the VMware HCL. Try installing using the Dell custom image for ESXi 6.0 U3. It should have all the necessary drivers from the hardware vendor -
thank you everybody, I was solved this problem, add RAM and install ESXi 6.5