Bricked Lumia 925 - Phone doesn't show up in Device Manager

Hi everyone,
I bricked my phone yesterday, while installing the WP 10 Preview.
It first showed up as QHSUSB_DLOAD (after red screen and stuff) while trying to recover it with WPRT 2.1.1, but now, after ejecting the device, it is not detected at all when I connect it to my laptop (running Windows 10).
The phone is fully charged (left it charging the whole night) and I don't really know what to do next.
Any ideas?
Thanks,
Iacopo