Please look at other thread before asking... especially this one
G4 devices are known to have two things in common :
- IPL/SPL are untouchable and with version number ending with .0001 (or so)
- they are CID locked (wish would only allow HTC to flash roms)
G3 Rom comes with IPL and SPL in. So if you try to flash it onto a G4 device, you may brick it by altering the original IPL/SPL. This is known to be hard to do, btw... don't do it. Also, in case of failed flashing, the IPL/SPL are the only things that could save you.
So you should try flashing G4 rom only.
Unfortunately, the CID lock makes it hard to flash any rom you'd like. Only a couple of ROMs are flashable on G4+CID devices
Loaded with 911-Desire