Without hacking, the TivoHD will only work with the MyDVR Expander. With hacking, you can use any eSATA disk you want. There's a eSATA TiVo FAQ around somewhere that goes into the details of what you need to do. Only the TiVo Series 3 will let you use any eSATA hard drive without hacking.

I have purchased the InstantCake but I'm having issues with my computer.
Disk Boot Failure, Insert System Disk And Press Enter
The only thing I can come up with is the verions Bois or computer is too old. Is there any way to upgrade from a laptop?
Series 2 standalone
Packard Bell wind 98
I have change the system to boot from CD rom.

Thanks