Minecraft wiki entry for Historical_effects, associated text: Between Alpha v1.0.1 and Beta 1.7.3 inclusive, the first distortions of redstone wire can be seen beyond 262,144 blocks. After this point, if redstone wire climbs a block face perpendicular to the direction 262,144 blocks are exceeded on, it will appear in the same plane as that block face, resulting in major z-fighting. This effect remains like this until 16,777,216 blocks, where error exceeds a full block.