Sorry for not getting round to this last night
You'll need to flash a recovery image, you can get TWRP from here:
TeamWin Projects - TWRP 2.6 - HTC One X (International / Tegra 3 / EndeavorU) | TeamWin
Download the img file and place it in your fastboot folder. Boot to fastboot on your phone, connect it to your PC and type:
Code:
fastboot flash recovery XXX.img
XXX being the name of the file you downloaded.
Let it complete, reboot back to your bootloader and select recovery. You should be taken in to TWRP recovery.
On your PC, you'll then want to head here:
[ROM] Android Revolution HD 31.3 | High | HTC One X > XDA
Follow the download links and download ARHD for the One X. Open (don't extract) the zip file and look for a file called boot.img. Place that in your fastboot folder.
Back to your phone, connect it to your PC then in to TWRP, select Advanced and there should be an option for mounts and storage. Select that, then mount USB. The phone should appear as an external drive on your PC?
Copy the zip file over to the phone, unmount, disconnect and go to the wipe menu in TWRP and select Factory Reset.
Once done, go back to the main menu and select Install Zip from SD Card. Choose the ARHD zip you just copied over, confirm and let it do what it needs to do. When it's finished, you want to reboot back to the bootloader, connect your phone to the PC again and flash the boot image with the following commands.
Code:
fastboot flash boot boot.img
Let it flash, then type:
Reboot.
It might take a while (10 mins or so), but you should boot up in to Android Revolution.