This is my first post here, but I have been messing with xboxen since virtually day one. I have never seen a definitive post on the net about whether this particular upgrade is doable and exactly what hardware will work, so since I just managed to accomplish it I thought posting my details might help others out.
WHAT YOU WILL NEED
1. SATA harddrive. I assume there are other drives that will work as well, but I chose to use a
Western Digital Caviar GP WD10EACS 1TB. It proved to be lockable so it will work for either modchip users or those with softmods. It is also very quite and runs quite cool to the touch. Regardless, you will need LBA48 support in your bios or a softmod which supports it such as nkpatcher (I use nkpatcher 11).
2. SATA to IDE adapter. Again, there may be other adapters that work, but I know this one does:
SABRENT SBT-STDB IDE Ultra ATA-100/133 to SATA Port Mini ConverterThats it really. I wont bother with a step by step as no trickery is required, the basic howtos for a harddrive upgrade will work fine. I used xboxhdm v1.9 and followed the normal procedure which can be found on this site. I used xbpartitioner and chose to split the free space across F and G using 32KB clusters. I ended up with 2 496GB partitions, and have completely filled up one of them with no corruption issues.
Happy upgrading!