C2758 - What is BIOS POST code 42
I have a C2758, which is nearly 3 years old…well, I did before it crashed (ironically, it happened just hours after I ordered a XG-1541 to finally set up redundancy for my home office).
After figuring out it was a hardware issue, I watched the boot process. It gets stuck at BIOS POST code 42.
I could not find an authoritative reference for POST code 42 (although one source said it is the answer to life, the universe, and everything). I did not see a Supermicro-provided list of codes, nothing in the motherboard manual, and the random internet searches had multiple possible error codes depending on the BIOS version (which wasn't helpful when it gets stuck before I can see the BIOS version).
I am hoping to determine whether I purchase a new motherboard (The included MB is a Supermicro A1SRi-2758F, which is readily available from retailers), new RAM, or if there is a different failed part, as I'd like to keep it around for redundancy.
Thanks for your assistance!
ivor last edited by
IIRC something to do with the drive you're using.
Thanks - it looks like that could be it, but just for the sake the the thread, the issue could not be entirely isolated to the HD, and may [also?] be something else
After additional troubleshooting, which included switching RAM chip slots (same chips, swapped slots), and a replacement SATA HD [using the existing power/SATA cables], I was able to get it to the BIOS setup screen, change IPMI settings, and install a clean install from an IPMI virtual CD: pfSense-CE-2.3.3-RELEASE-amd64.iso
The reason I am not certain that the HD is the [only] cause, is that after switching the HD, I was able to view the BIOS system event logs, and there were 20 low CMOS battery alerts.
1 1970/01/01 00:01:34 VBAT Voltage Lower Critical - Going Low - Asserted
2 1970/01/01 00:01:34 VBAT Voltage Lower Non-Recoverable - Going Low - Asserted
19 1970/01/01 00:31:22 VBAT Voltage Lower Critical - Going Low - Asserted
20 1970/01/01 00:31:22 VBAT Voltage Lower Non-Recoverable - Going Low - Asserted
[the 1970 dates usually indicate that CMOS lost its date/time when AC power was removed]
I replaced the CMOS battery (first testing the new battery, which measured 3.3 v) and rebooted several times (via IPMI). The VBAT remained reading 1.68 v. At one point it briefly read "within range", but by the time I could see the voltage measurement (on a different IPMI web page), the reading was 1.68 v.
For the sake of isolating the cause, I plugged back in the original HD (which was the 80 GB Intel SSD that originally came with the server), and got Post code 42 again… so there does seem to be an error with the original drive, but there may also be another issue related to BIOS/CMOS/Battery.
Since there may be an issue with the MB, it looks like the best option will be to replace the MB, too.
@pvuchetich Do you able to solve the problem? I have the same one.
Exactly the same code? Same hardware?
If you have an expansion card in there try removing it as a test. Does it POST without that?
@stephenw10 the board is A1SA7-2750F
without ANY additional hardware. Tested with ECC/None-ECC memory, сhanged battery - nothing helps - code 42.
If I leave A1 memory slot empty - code 19.
IPMI is locked with unknown password, so I not able to check anything with it.
@Caersar007 one thing you could try is to pull power to the system, and unplug the system FAN1 (CPU FAN) and see if it boots. Just watch your temperatures..
I had a failed FAN1 which was also giving me a POST code 42 on a A1SRI-2558F-O and after removing power to the system, and then also removing the FAN1 connector to the failed fan it was able to boot.
The case I have it in is designed to be fanless, but I had a small fan above the CPU to keep it cooler.
I'm not sure if the actual CPU temperature got too hot when the fan failed and the pfsense box went offline, or if it was a precautionary failure to prevent it.
Hope that helps.
Board won't soft-reboot without hanging at the code 42 boot code now.
Sending in A1SRI-2558F board for RMA to Supermicro with "C2000 RMA" as the problem description. Seems like it relates to the C2000 clock issues coming back from 2017 to bite upon reboot/hang :(
Luckily I had just rebuilt a pfsense replacement and also had a very recent config backup for testing it, so I was ready to go and swapped it out.