[solved]2504 Dock for T61 ... hardware fault?

[sdi-p]

I have two docks, both are model 2504
outward appearance is identical
#1. S/N M113VJ7 08/10
ASM P/N 42W4639
FRU P/N 42W4638

#2. S/N M111KDR 08/09
ASM P/N 42W4633
FRU P/N 42W4632

Running LMDE (Linux Mint Debian Edition)
#1 works as expected

#2 when I unplug AC display and keyboard freezes. reconnecting AC does not help. Reboot and it works fine without AC plugged in, connect AC is OK, disconnect and it freezes agai.
I have 3 T61s. it is the same with all three.

Is this a hardware fault or a change in design?

thanks, Peter

[sdi-p]

I have Windows 7 on one of the T61s. I tried that and same thing, the famous windows BSOD when it lost AC power

[dr_st]

Is there a setting in the BIOS to disable legacy devices (parallel/serial port) on the mini-dock? This was the culprit for the T60, but I am not sure that the T61 has a similar thing.

[sdi-p]

Is there a setting in the BIOS to disable legacy devices (parallel/serial port) on the mini-dock? This was the culprit for the T60, but I am not sure that the T61 has a similar thing.

Great idea, I can check. thanks

However my Logic says no, the other dock (#1 above) does not behave this way (S/N M113VJ7 08/10). I suspect that the design may have changed: problem dock = S/N M111KDR 08/09.

I will check the BIOS

[sdi-p]

Is there a setting in the BIOS to disable legacy devices (parallel/serial port) on the mini-dock? This was the culprit for the T60, but I am not sure that the T61 has a similar thing.

thanks dr_st

yes, there is a BIOS setting, enabled by default on all three. I checked one on the dock, no more problem.

(this old man's logic fails again)