Comment by jdblair
1 year ago
I remember when I built a new PC, with some socket 370 pentium or another, around 2002.
I ran an i2c probe to find the addresses to read the fan tachometer. The scan wrote some bits that irrecoverably messed up the firmware, the board wouldn't boot and I replaced it.
Asus must have anticipated trouble because their boards from that time period hide I2C bus away by default :) You have to do special port knocking incantation to expose it https://www.vogons.org/viewtopic.php?p=1173247#p1173247
>They share i2c bus between clock generator/monitoring chip and ram SPD using a mux. If you switch this mux and forget to switch it back computer will have trouble rebooting because bios blindly assumes its always set to clock gen.