Revisions 1.2-1.5
Revisions 1.2 - 1.5
The middle of the Original Xbox production run, revisions 1.2 through 1.5, represents a series of incremental cost-reduction and component changes. From a modder's perspective these boards are similar enough to be treated as a group.
Modding options
All four revisions support the full range of methods. You can apply the ENDGAME softmod recommended, perform a TSOP flash to install a custom BIOS, or fit a modchip such as the OpenXenium or Aladdin XT/XT Plus2. Nothing in this guide is off-limits for these boards.
What differs across the range
The changes between 1.2 and 1.5 are mostly internal: revised components, layout tweaks, and manufacturing simplifications. None of these meaningfully change how you mod the console, which is why the guide groups them together.
These boards are still old enough that the clock capacitor can leak. Inspect it before and during any case-opening work, since corrosion from a leaking cap can cause hard-to-diagnose boot problems.
Recommendation
The softmod is the simplest and safest entry point and needs no soldering. If you want a clean modchip-free setup with a custom BIOS, TSOP flashing is still available on these revisions, an option that disappears on the later 1.6 boards.
EEPROM first
Whichever route you take, back up the EEPROM before you begin. The HDD key cannot be recovered if lost.