I have been trying to do a recovery on my intel compute stick by pressing F8 when it restarts but it gives me some strange error and asks me to insert the windows setup disk for repairing. Also, I made a bootable usb stick with windows 8.1 32bit on it and when I restart the compute stick I cannot even see any usb boot options. I have already changed the BIOS to boot from Ubuntu but that still doesn't help. I have downloaded the windows 8.1 from the Microsoft mediacreationtool available on the following link.
And further I use rufus tool to create the bootable usb with windows 8.1 on it. I followed this page.
It seems that the partition where Windows image is located was deleted since the OS is embedded to the Compute Stick there is not option from our end to recover it, so my recommendation is to contact Intel Customer Support for warranty replacement of your Compute Stick. You can use Support Options to do that, Contact Support.