SGI: Hardware

joerg wrote:

Oskar45 wrote:

Dr. Dave wrote: Since the chips 'read' OK, one can assume that either the analog input to the chip on the offending line is bad (implying a chip problem), the voltage reference for the device is bad, or the origin for the derived voltage is bad.

Did you ever consider the possibility that the chips themselves might indeed be ok but the checking /algorithm/ is faulty?

Shouldnt than sgi can fixed that with a firmware upgrade? According to the post sgi replaced the boards.

Exactly, that's what happened in my case - I simply got a new motherboard.

If it was software-only, as Joerg points out, SGI would have just reflashed the boards and saved the time and cost of replacing them. There has to be a hardware funky on the board that causes the monitoring to die over time.

Again, if someone with a 'new' Fuel mobo can take a picture around the 'Timekeeping Snaphat' chip (should be next to power supply stuff and the Dallas chip) I can do a comparison with the 'old' boards. Maybe it's just a faulty run of Dallas chips, who knows?

It seems that there are two seperate issues here with Fuel - (1) the environment monitoring can go south and (2) the PSU can fail with overvoltage. In Obelix's case, it seems to be the PSU since he has tested it with a VOM. Perhaps this could go somewhere in a Fuel FAQ or a SGI PSU FAQ (since they seem to have problems...)
along with the enviromental monitoring outcome (definitely recommend the use of a good DMM to verify PSU accuracy before disregarding EnvMon warnings).

I don't have a Fuel available, but it seems like a good thing for hobbyists to have would be a pinout of the Fuel power connector so it can be replaced by generally-available sources. (provided the ratings are correct). Anyone with a Fuel, VOM, and bit of time want to oblige?

In my case, the local SGI support couldn't say for sure whether it was hardware or firmware related - so I just got a new board.

Has anyone figured out the Fuel PSU pinout for this yet?