Modchips
A modchip is a small add-in board that gives the Original Xbox a modified BIOS independent of the hard drive and the onboard flash. It is the most robust route to a modded console, because the modification lives on dedicated hardware that you can switch on or off.
Where a modchip lives
Modern modchips attach to the internal LPC header, a row of pads on the motherboard exposed for exactly this kind of expansion. The chip taps that header to inject its own BIOS at boot.
The 1.6 caveat
On most console revisions the LPC header is ready to use. On the 1.6 revision, however, the header is incomplete and must be rebuilt by adding a missing component before a chip will work. This is a known, well-documented step but it does require soldering.
Why pick a modchip
- Resilience because the mod does not depend on a softmodded dashboard that could be corrupted.
- Switchability so you can boot stock or modified as needed.
- Works on 1.6 where TSOP flashing is impossible.
Popular choices
The OpenXenium is a fully open-source modchip, while the Aladdin XT and XT Plus2 are affordable, widely-available options. Both install on the LPC header and are covered on their own pages.
Always back up the EEPROM before installing any chip, and verify which console revision you own so you know whether the header needs rebuilding.