Hi,
I just put a new hard drive in my unit. With the new hard drive in the unit, it would be in a reboot loop until I put in the firmware cd (downloaded and burned to a disk). It then read the cd and installed the firmware and the loader just fine

here's the steps:
1. Power up the recorder and open the DVD tray.
2. Insert the prepared upgrade CD-ROM.
3. Close the tray and the recorder will auto read the disc.
4. Upon recognize the disc, the local display of recorder will show "FLASH 1". The TV screen will show a dialog box titled "Disc Upgrade".
5. Note: The recorder will indicate "Unknown Disc" in the following 2 situations.
- When the software upgrade is not meant for your recorder (Check the applicable models above).
- Problem with writing of CD-ROM. Try again with a different CD-ROM if possible.
6. To proceed with the Upgrade, press on the remote control. You can cancel the upgrade at this point by navigating to CANCEL button on TV and pressing on the remote control.
7. If you proceed with the upgrade, the upgrading status will be shown on the TV screen.
8. The whole process takes about 1 minute after which the local display of recorder shows "DONE" and the dialog box on TV screen indicates successful upgrading. The tray will be ejected.
9. Remove the CD-ROM before pressing on the remote control. The recorder should close the tray and restart automatically after about 10 seconds.
10. Note: Do not press any buttons or interrupt the mains supply during the entire upgrading process, otherwise the recorder may become defective.
11. Note: Sometimes, the recorder does not close the tray. Do not be alarmed. Simply press on the remote control to wake up the recorder and the tray will close immediately.
12. It is better to power off and on the recorder again after software upgrade before using the recorder.
Now I have 500gb and the unit it working better than ever

Hope this helps people trying to replace the hard drive!