Screen replaced - digitizer cable broke, rest of phone ok?

Hi all,

I had a working iPhone 4 with badly cracked screen. I just replaced the full front assembly (digitizer+lcd+screen), but I accidentally broke the digitizer ribbon/flex cable (stupid stupid...).

This would cause the digitizer to be not working, but the rest of the phone+screen should be working, right?

When I now try to start up the phone, nothing happens. (also hard reset isn't working)

When I connect it to USB/Itunes, the phone gets recognized, vibrates/beeps every 5 seconds and the screen goes white after a while.

When I try a hard reset (home/onoffbutton) while connected to Itunes, it will perform a restore and software update.

When I then disconnect the phone from USB, the screen stays white. I can then switch the screen on and off with the power button, it makes the 'click' sound.

I am now doubting whether I would buy another replacement screen to replace this broken digitizer one, would this make the phone work again? Or is this thing done for (and only an expert could invest in it and make it work again)

Thanks in advance!

Kind regards