Hi Elf,



Did you ever get more info/time on this Tezro 1.8v issue?



I really forget what happened (I looked at an old email to even remember this happened...it's been that long since I've used this system).



My first Tezro does this a couple moments after startup (log shown below), but did start to the PROM and then shortly shutdown. When I bought it second-hand it was working for nearly a year, upgraded RAM from 4GB to 8GB (complete module replacements), added a bunch of PCI Cards, then had a 5V rail dip issue (temporarily resolved by removing my Adaptec firewire card that pulled heavy on my 5V rail. But I think this started to happen (or maybe it resolved with the 5V issue…not sure).



So I guess I have this too…a lot. I want to concentrate on this stuff in December when I’ll hopefully be able to buy a late model curve tracer to test components. For now I have the voltage dip and the firmware forces a PSU shutdown. Seems to be exactly what you’re describing at the end of your post. Did you replace the filter cap in that 1.8v buck convert section and see if this went away? I assume that’s what’s needed because it starts out great, then dips, and I know a lot more than I did back then about this power electronics stuff. So I feel better about doing work on this issue later this year.



But since you saw the same thing, was wondering if any progress was made on this? Obviously, the regulator IC isn’t blinking out or anything, but low voltage on a buck converter is normally a sign of crap smoothing (DC average) by the final cap (correct me if I’m mistaken).



Any new info would be greatly appreciated!







LOG from like 2011 (Dual 800Mhz Tezro Deskside, I know the firmware is old, never really loaded Irix beyond 6.5.19 on this due to hardware issues that cropped up soon after.):







INFO: Cannot enable VRM: 9



INFO: Cannot enable VRM: 10



INFO: Cannot enable VRM: 11



SGI SN1 L1 Controller



Firmware Image B: Rev. 1.32.6, Built 09/27/2004 14:40:25





001c01-L1>



001c01 ATTN: Cooling system stabilized



001c01 ATTN: 1.8V low fault limit reached @ 1.199V.



001c01 ATTN: brick auto power down in 30 seconds



001c01 ATTN: brick auto power down in 25 seconds



001c01 ATTN: brick auto power down in 20 seconds



001c01 ATTN: brick auto power down in 15 seconds



001c01 ATTN: brick auto power down in 10 seconds



001c01 ATTN: brick auto power down in 5 seconds



001c01 ATTN: brick is powering down now!